<?xml version="1.0" encoding="UTF-8"?><rss xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:content="http://purl.org/rss/1.0/modules/content/" xmlns:atom="http://www.w3.org/2005/Atom" version="2.0" xmlns:itunes="http://www.itunes.com/dtds/podcast-1.0.dtd" xmlns:googleplay="http://www.google.com/schemas/play-podcasts/1.0"><channel><title><![CDATA[Microfounded]]></title><description><![CDATA[An infovore on a quest for discovery: writing about economics, the social sciences, culture, AI, philosophy, and more.]]></description><link>https://www.ciaranmarshall.co.uk</link><image><url>https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png</url><title>Microfounded</title><link>https://www.ciaranmarshall.co.uk</link></image><generator>Substack</generator><lastBuildDate>Thu, 28 May 2026 06:59:33 GMT</lastBuildDate><atom:link href="https://www.ciaranmarshall.co.uk/feed" rel="self" type="application/rss+xml"/><copyright><![CDATA[Ciaran Marshall]]></copyright><language><![CDATA[en]]></language><webMaster><![CDATA[microfounded@substack.com]]></webMaster><itunes:owner><itunes:email><![CDATA[microfounded@substack.com]]></itunes:email><itunes:name><![CDATA[Ciaran]]></itunes:name></itunes:owner><itunes:author><![CDATA[Ciaran]]></itunes:author><googleplay:owner><![CDATA[microfounded@substack.com]]></googleplay:owner><googleplay:email><![CDATA[microfounded@substack.com]]></googleplay:email><googleplay:author><![CDATA[Ciaran]]></googleplay:author><itunes:block><![CDATA[Yes]]></itunes:block><item><title><![CDATA[Smartphones and fertility: a simple model]]></title><description><![CDATA[Preliminary calibrated estimates to explain my skepticism]]></description><link>https://www.ciaranmarshall.co.uk/p/smartphones-and-fertility-a-simple</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/smartphones-and-fertility-a-simple</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Sat, 23 May 2026 15:22:01 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p>Previously, I have been a longstanding sceptic of the smartphone theory of everything, including the notion that they are partly responsible for the global fertility decline<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-1" href="#footnote-1" target="_self">1</a>. This argument has always <a href="https://www.ciaranmarshall.co.uk/p/february-2026-links?utm_source=publication-search">struck me as model-free</a>, yet the sort of hypothesis you need a model for<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-2" href="#footnote-2" target="_self">2</a>. Phones raise the value of the outside option yet lower search and matching costs whilst increasing the efficiency of matching<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-3" href="#footnote-3" target="_self">3</a>. Without a model, we cannot come close to knowing what the net effect is. This post provides such a model using a search-theoretic approach.</p><p><strong>Our model</strong></p><p>Suppose that the rate at which matches occur is described by an exogenous real-valued &#966; and match quality (and surplus) an exogenous real-valued q. The number of matches M is a Poisson process of rate &#966;. For simplicity, q is normally distributed i.i.d with mean zero and variance of one<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-4" href="#footnote-4" target="_self">4</a>. Individuals will form matches if q is weakly preferred to their reservation utility, which is a function of their outside options and the expected NPV of all possible matches preferred to this match:</p><div class="latex-rendered" data-attrs="{&quot;persistentExpression&quot;:&quot;R=b_0+&#946;&#966;\\int_{0}^{\\infty} 1-F(q) \\, dq&quot;,&quot;id&quot;:&quot;VGJMSAAKSL&quot;}" data-component-name="LatexBlockToDOM"></div><p>where b is the outside option and F(q) is the C.D.F. of q.</p><p>Phones increase the value of the outside option to b&#8217;=b0+&#949;, whilst &#966; increases. The number of matches is M = &#966;(1-F(R))N for N being the total number of those seeking a romantic relationship<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-5" href="#footnote-5" target="_self">5</a>. So &#916;&#966;&gt;-&#916;(1-F(R)) for phones to increase matching via my proposed channel of reduced matching barriers, and vice versa for the smartphone theory to hold. Can we introduce some numbers to arrive at a precise conclusion? Yes we can. Let's now turn to a calibration exercise.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><p><strong>Calibration</strong></p><p>For over a decade now, online dating has been <a href="https://ideas.repec.org/a/nas/journl/v116y2019p17753-17758.html?utm_source=chatgpt.com">the most common channel</a> via which relationships form. <a href="https://www.pewresearch.org/short-reads/2023/02/02/key-findings-about-online-dating-in-the-u-s/?utm_source=chatgpt.com">About 30% of US adults have used online dating apps</a>, and <a href="https://www.pewresearch.org/internet/2020/02/06/the-virtues-and-downsides-of-online-dating/?utm_source=chatgpt.com">12% are in romantic relationships</a> as a direct result of online dating. Considering all the online platforms via which matching can occur, and those platonic friendships online that eventually develop into romantic relationships, these numbers understate the extent to which the internet facilitates matching. On the other hand, these figures are heavily US-centric, whilst fertility has fallen worldwide. Nonetheless, I think the overall effect has been to increase the matching rate, and so therefore I will use a rise from &#966;=1 to &#966;=1.3 as my choice in parameters for this calibration<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-6" href="#footnote-6" target="_self">6</a>. </p><p>There is also <a href="https://www.aeaweb.org/articles?id=10.1257%2Faer.100.1.130&amp;utm_source=chatgpt.com">some evidence</a> that people prefer matches formed online relative to offline, and if anything revealed preferences from dating behaviour shifting to online imply that Ariely et al (2010) likely understate the improved matching efficiency. However this reduces acceptance rates in the model, as people become more selective given that reservation utility is higher. Perhaps a change in 1-F(q) from 0.3 to 0.2 is plausible.</p><p>The notion that phones are a substantial gain in the outside option value is uncontroversial, and perhaps this rise is up to around half a standard-deviation point of average match surplus. I will use b0=0.2 and b&#8217;=0.5.</p><p>From the model, using our chosen parameters, these are the values of reservation utility prior to smartphones. R is 0.494 at a discount rate of 2%, and 0.485 at a 5% discount rate. After smartphones, if &#946;=0.98 then R=0.7548 and if &#946;=0.95 then R=0.747.</p><p><strong>Why my priors imply null effects with high uncertainty</strong></p><p>With these numbers, the cheaper matching effect roughly outweighs the effect of the gains to the outside option, albeit this result is highly uncertain and sensitive to the choice of parameters involved. Adjusting for this, the model implies that the effects of smartphones on number of matches is close to zero yet almost certainly non-significant and not robust.<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-7" href="#footnote-7" target="_self">7</a> </p><p>One significant limitation of this exercise however is that I have not estimated a regression structurally to inform these parameter values of match rates, changes to cross-country match rates after smartphone adoption, and an outside-option proxy (aggregating a weighted mix of app usage intensity, time on social media or dating apps, survey data on relationship quality, and so on). If there exists high-quality datasets for this empirical exercise, perhaps a staggered DiD is possible, and one can then feed the estimates into this model. More research on this topic is certainly necessary, otherwise model-free and <a href="https://x.com/i/status/2056715277228732799">empirically slack</a> commentary will prevail in this discourse.</p><p class="button-wrapper" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/p/smartphones-and-fertility-a-simple?utm_source=substack&utm_medium=email&utm_content=share&action=share&quot;,&quot;text&quot;:&quot;Share&quot;,&quot;action&quot;:null,&quot;class&quot;:null}" data-component-name="ButtonCreateButton"><a class="button primary" href="https://www.ciaranmarshall.co.uk/p/smartphones-and-fertility-a-simple?utm_source=substack&utm_medium=email&utm_content=share&action=share"><span>Share</span></a></p><p><strong>So what explains the baby bust?</strong></p><p>In general<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-8" href="#footnote-8" target="_self">8</a>, I believe that factors such as high housing costs (a result of persistent NIMBY policies across the West) and declining maternal and child mortality (meaning <a href="http://&quot;Every time a woman gets pregnant she incurs significant costs&quot;. &quot;If you tried for seven kids, but only expected three&quot;, often more survived. You needed to plan for all, &quot;even if the expected value was lower&quot;.">people that previously internalised the risk of death are adjusting</a> their planned births downwards) are the most compelling explanations. Less kids amongst families already giving birth <a href="https://x.com/i/status/2056659389084225905">seems</a> to dwarf the impact of rising childlessness. </p><p>The cross-country data clearly rejects the thesis that feminism (in particular increased female labour-force participation) is driving the decline, as fertility is collapsing in highly conservative societies such as Italy and China, and generally is declining regardless of how feminist a nation is<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-9" href="#footnote-9" target="_self">9</a>. To the extent that the motherhood penalty is higher in such societies, this should actually <a href="https://chatgpt.com/share/6a083969-1b4c-83eb-af62-0cd9834aee13">reduce TFR in equilibrium</a>. </p><p>However there are some cultures where TFR is stable and often high. The Amish and Haredi Jewish communities, and to a lesser extent Central Asians, are the most commonly cited examples. Although fertility is declining in sub-Saharan Africa and the Muslim world too, those TFRs tend to be higher than those in Western or East Asian societies. Hence &#8220;cultural&#8221; factors likely play some role (<a href="https://x.com/i/status/1939786834487517588">with spillovers</a> <a href="https://x.com/i/status/2056739256094052683">observed</a>), yet at this stage features as nothing more than <a href="https://open.substack.com/pub/alexnowrasteh/p/the-culture-crutch?utm_source=share&amp;utm_medium=android&amp;r=56swa">a residual</a> lacking precise mechanisms or estimates - instead being a kitchen-sink for our (often ideologically motivated) priors.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-1" href="#footnote-anchor-1" class="footnote-number" contenteditable="false" target="_self">1</a><div class="footnote-content"><p>To be clear, the mechanism commonly proposed is that phones increase the relative pleasure of solitary activity, leading to less relationships forming. Phones can also act as a substitute to sex and raising children within a relationship, but to be tractable, this post will focus entirely on the former mechanism. Incorporating the latter channels probably increases the estimates of the smartphone cost to fertility.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-2" href="#footnote-anchor-2" class="footnote-number" contenteditable="false" target="_self">2</a><div class="footnote-content"><p>Also improvements in smartphone technology are likely correlated with that in IVF, which is undoubtedly pro-fertility, yet today I want to isolate the impact of smartphones in particular.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-3" href="#footnote-anchor-3" class="footnote-number" contenteditable="false" target="_self">3</a><div class="footnote-content"><p>In the sense that matches (platonic and romantic relationships alike) reflect preferences better. People who meet online are more likely to have interests, traits, and values in common than random matches. People prefer these matches than those awkward ones where they hardly have anything in common. In this sense, the efficiency is both allocative and Paretian.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-4" href="#footnote-anchor-4" class="footnote-number" contenteditable="false" target="_self">4</a><div class="footnote-content"><p>Admittedly my results are sensitive to this assumption. Online dating tends to follow a lognormal or power law process, in that matches and response rates tend to be incredibly skewed to the most attractive (so highest quality) matches. The greater the skew and kurtosis, the more likely that online dating reduces total matches. However, dating apps are not the only means via which people interact and meet online. Hence by considering all the (social media) platforms via which matching can occur, my assumption of using a Gaussian process is justified. Alternative social media platforms offset the inequalities inherent in online dating apps.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-5" href="#footnote-anchor-5" class="footnote-number" contenteditable="false" target="_self">5</a><div class="footnote-content"><p>Of course phones increase the value of nonparticipation too, but for simplicity we'll assume that inactivity is zero, which is sufficient for modelling this margin.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-6" href="#footnote-anchor-6" class="footnote-number" contenteditable="false" target="_self">6</a><div class="footnote-content"><p>Non-economists would probably consider these chosen values as rather arbitrary, and indeed calibration is a large source of dispute for each particular paper. However this process is at least more precise and rigorous than simply asserting that phones decrease matching, and allows for transparency in assumptions and estimates.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-7" href="#footnote-anchor-7" class="footnote-number" contenteditable="false" target="_self">7</a><div class="footnote-content"><p>Accounting for footnotes 1 and 4 possibly turns this into a negative effect, however still probably non-significant and not robust given the sensitivity of these estimates to the assumptions, calibration, and mechanisms used.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-8" href="#footnote-anchor-8" class="footnote-number" contenteditable="false" target="_self">8</a><div class="footnote-content"><p>The links in my link pages inform these conclusions, alongside any others provided here.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-9" href="#footnote-anchor-9" class="footnote-number" contenteditable="false" target="_self">9</a><div class="footnote-content"><p>Indeed there is an ulterior motive amongst many in the pro-natal crowd to use this as an excuse to control female bodies and subjugate women&#8217;s rights and autonomy. Needless to say, none of this is helpful to resolving what I consider to be humanity's greatest existential threat. This is mostly a positive rather than normative exercise though, so my opinion is relegated to the footnotes for those interested.</p></div></div>]]></content:encoded></item><item><title><![CDATA[ChatGPT role-plays myself]]></title><description><![CDATA[I asked ChatGPT 5.5 to rewrite Imas&#8217; post in the style of myself.]]></description><link>https://www.ciaranmarshall.co.uk/p/chatgpt-role-plays-myself</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/chatgpt-role-plays-myself</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Wed, 20 May 2026 17:05:33 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p>I asked ChatGPT 5.5 to rewrite <a href="https://x.com/i/status/2056721711282725045">Imas&#8217; post</a> in the style of myself. This is the post:</p><blockquote><p>&#8220;Here is my take on AI writing. I don&#8217;t personally like it, but that&#8217;s taste, and I&#8217;m sure it&#8217;s possible to post train the model to write &#8220;well&#8221; (conditional on some notion of taste). But that&#8217;s besides the point for me: AI writing makes all writing sound the same. If you use AI enough it takes about 30 seconds into a piece to realize it, and then my brain kind of shuts off because that&#8217;s the 20th time that day I&#8217;ve read the same cadence and tone. </p><p>For code it&#8217;s fine since the only goal is to get it to run. But if you&#8217;re trying to write, eg a substack, part of the goal is to keep the reader engaged and connected to you&#8212;the writer&#8212;and for that you need to have your own &#8220;voice&#8221;."</p><p>AI for writing is a shortcut. And for some purposes it makes a lot of sense. But I think for writing it is in the interest of the writer to differentiate themselves by using their own voice. Especially as more and more people start using AI.&#8221;</p></blockquote><p>This is the result:</p><blockquote><p>"My view on AI writing is perhaps less "AI is bad" and more "AI compresses variance".</p><p>I don't personally enjoy reading most AI-generated writing, although that is largely a matter of taste. I assume it is entirely possible to post-train models into writing "well", conditional on whatever objective function one has in mind.</p><p>But that isn't really my concern.</p><p>The issue is that AI writing increasingly converges toward a similar cadence and tone. After enough exposure, one develops a kind of detector. Roughly thirty seconds into reading something, you realise: I've already read this nineteen times today.</p><p>And then my brain quietly switches off.</p><p>Code feels different. The objective function for code is fairly clear: does it run? Does it solve the problem? Elegant code is nice, but ultimately secondary.</p><p>Writing serves a different purpose. If you're writing a Substack, an essay, or even a long X post, part of the output is not merely information transfer. The writer themselves is part of the product. You want readers to remain engaged, but also to feel some connection with the person behind the words.</p><p>That requires a voice.</p><p>AI is obviously useful as a shortcut. For some tasks it is a very good shortcut. But I increasingly suspect that for writing, as more people adopt AI, preserving your own style becomes more valuable rather than less.</p><p>Differentiation compounds."</p></blockquote><p>I'm not impressed. The first time I've been dissappointed with Chat, which is a large signal on the quality of AI prose.</p>]]></content:encoded></item><item><title><![CDATA[AI employment effects: a primer]]></title><description><![CDATA[All your questions on what AI means for your job answered]]></description><link>https://www.ciaranmarshall.co.uk/p/ai-employment-effects-a-primer</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/ai-employment-effects-a-primer</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Sat, 16 May 2026 17:37:16 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p>Will AI automate your job? Will your income increase? What happens to the labour share? Is AI complementary to labour inputs or a substitute? What are the theories that can answer these questions? This post will hopefully answer at least some of these questions by focusing on two prominent papers. I may update this as new theoretical insights are introduced. Hence one should see this as an indefinitely ongoing project.</p><p><strong>Jobs as task bundles</strong></p><p>I will start by introducing the Coasian notion of jobs as a continuous bundle of distinct and discrete tasks: inspired by <a href="https://www.dropbox.com/scl/fi/r98qemfwqmyc108mlp47i/2026.03.30-Bundles-WP-Version.pdf?rlkey=jdb3y32eiww5pplr5316uj2wa&amp;e=7&amp;st=galfrrki&amp;dl=0">Garicano et al (2026)</a>. The idea is that exposure measures can be misleading as jobs aggregate multiple tasks rather than being uniform in composition. Some of these tasks are complementary, and some substitutes. Different inputs can complement some tasks and substitute others. Bottlenecks in enacting one task can delay the entire bundle operation<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-1" href="#footnote-1" target="_self">1</a>. Therefore exposure measures assume a linearity that simply does not exist.</p><p>Crucially, the effects of AI in this model depend on how tight the bundle is. If the bundle is weaker, so it&#8217;s cheaper to break the bundling, AI automation of some tasks are more likely to narrow the job boundary and pose greater disemployment effects, and vice versa. In fact, if the bundling is sufficiently strong and bottlenecks tight, then AI automation improving productivity in some tasks may enhance the overall occupational productivity - leading to positive employment and wage effects.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><p>Consider <em>a job as a production function</em> of two tasks:</p><p>y = (q1^&#945;)(q2^(1-&#945;)).</p><p>Task one can be automated, whilst two cannot. There exists a time constraint, t1+t2&lt;=1 for nonnegative times devoted to tasks one and two respectively.</p><p>Two scenarios are now introduced. If bottlenecks are sufficiently tight such that task one can only be partially automated, then output is given by:</p><ol><li><p>y = ([{(&#956;(m))^(1-&#951;)}{t1s1}^&#951;]^&#945;)[t2s2]^(1-&#945;)</p></li></ol><p>where &#956;(m) is an increasing function of frontier AI capability m. Si denotes the share of the job represented by task i. The shares are equivalent to the comparative advantage of the worker with respect to different tasks; in other words his abilities (relevant later). &#951; gives the &#8220;human share&#8221; of output within a job. Notice that we have simply represented qi as a function of ti, si, and &#956;(m). Output remains Cobb-Douglas, with AI featuring as <a href="https://open.substack.com/pub/microfounded/p/a-primer-on-economic-growth?utm_source=share&amp;utm_medium=android&amp;r=56swa">labour-augmenting</a> technology.</p><p>If bundling is weak, then:</p><ol start="2"><li><p>y = (1-c)[{&#956;(m)}^&#945;]s2^(1-&#945;).</p></li></ol><p>Our employee focuses exclusively on task two. Task one is fully automated at cost c, which incorporates the bottlenecks and Coasian frictions discussed. Here, AI is not labour-augmenting but a distinct input in itself.</p><p><a href="https://open.substack.com/pub/siliconcontinent/p/a-new-years-letter-to-a-young-person?utm_source=share&amp;utm_medium=android&amp;r=56swa">As Garicano has noted</a>, when m is sufficiently high and c sufficiently low, more jobs converge to the weak bundling case. Eventually, this is how AI could replace most human labour. For simplicity, let&#8217;s call this AGI. Here we treat both m and c as exogenous, yet in reality, as m rises, c falls<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-2" href="#footnote-2" target="_self">2</a>. Nonetheless, <a href="https://open.substack.com/pub/aleximas/p/what-will-be-scarce?utm_source=share&amp;utm_medium=android&amp;r=56swa">social</a> and political-economy factors alone (as well as Hayek's famous coordination problem) will ensure that c remains strictly positive, as well as Moravec's paradox (although robotics capabilities are advancing too, albeit at a slower rate). Therefore <em>even with AGI, human employment remains positive</em>. Indeed, this is a recurring theme across all the models covered here. In other words, to maintain a future career, <em>look to sectors and invest in skills where humans still maintain a comparative advantage</em><a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-3" href="#footnote-3" target="_self">3</a>.</p><p class="button-wrapper" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/p/ai-employment-effects-a-primer?utm_source=substack&utm_medium=email&utm_content=share&action=share&quot;,&quot;text&quot;:&quot;Share&quot;,&quot;action&quot;:null,&quot;class&quot;:null}" data-component-name="ButtonCreateButton"><a class="button primary" href="https://www.ciaranmarshall.co.uk/p/ai-employment-effects-a-primer?utm_source=substack&utm_medium=email&utm_content=share&action=share"><span>Share</span></a></p><p><strong>If jobs are task bundles, what does this mean for wages?</strong></p><p>In scenario 1, our worker aims to maximise output<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-4" href="#footnote-4" target="_self">4</a> subject to his binding time constraint<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-5" href="#footnote-5" target="_self">5</a>:</p><p>t*1 = &#945;&#951;/(&#945;&#951;+1-&#945;), t*2 = (1-&#945;)/(&#945;&#951;+1-&#945;).</p><p>Both the output and human shares determine task allocation within a job. Raising either raises the time devoted to the corresponding tasks. This is attenuated by the cross-task implications: both tasks are essential for the job, yet allocating more time to one task reduces the time available on the other. By substituting into our production function, you get equilibrium output.</p><p>Wages are a function of revenue, Py. Let P=p1+p2, with pi simply being the share of value that task i contributes to production. p1q1 = &#945;Py and p2q2 = (1-&#945;)Py. In scenario 1, the worker gets the human share of revenue for task one.</p><p>We now arrive at one of the key results. <em>The wage effects differ according to whether AI is complementary</em> (the labour-augmenting scenario 1) <em>or a substitute</em> (scenario 2). &#969; = (&#945;&#951;+1-&#945;)Py or &#969; = (1-&#945;)Py for scenarios 1 and 2 respectively. The relevant shares determine the allocation of the wage across tasks and inputs, as is standard in perfect competition. Crucially, in scenario 1, as long as &#951; is positive, then &#945;&#951;+1-&#945;&gt;1-&#945;, so <em>wages are higher when AI is labour-augmenting relative to when AI is a substitute</em>.</p><p><em>There exists heterogeneity however in how workers will allocate across occupations depending on their abilities</em>. Let s*1 divide workers into low task one ability and high task one ability. Workers of low and high task one abilities hold s1&lt;s*1 and s1&gt;s*1 respectively. s*1 is:</p><p>s*1 = ([(1-&#945;)(1-c)/{(&#945;&#951;+1-&#945;)(t*1^&#945;&#951;)(t*2^(1-&#945;))}][{&#956;2(m)^&#945;}/{&#956;1(m)^(&#945;(1-&#951;))}])^(1/&#945;&#951;)</p><p>for &#956;i being frontier AI's contribution to output in scenario i. <em>AI substitutes weakly bundled tasks faster than it augments strongly bundled tasks given the coordination costs in AI adoption within a task</em>. s*1 is increasing in frontier capability and the output share of task two. s1 is decreasing in coordination costs. Increases in these are weighted by the human and output shares of task one however. Time constraints feature in the attenuation. <em>If and only if s1&lt;=s*1, their wages are weakly higher in weakly bundled than strongly bundled occupations</em> as they hold a comparative advantage in the former. Therefore <em>as capabilities advance and adoption accelerates, more workers will be exposed to automation</em>. By solving for the equilibrium, <em>whether overall wages increase for workers of low task one ability depends positively on the output share of task two</em>. In general, there is high ambiguity and uncertainty on the long-run earnings implications here, at least for those not holding capital.</p><p><strong>So how does AI affect employment in task bundling?</strong></p><p>Let U&#8217;/P denote the relative price of participation in labour markets, with U&#8217; the utility from the outside option. Households maximise a value function incorporating U&#8217; and wages in the strongly and weakly bundled cases, which depends on s, m, P, c, and U&#8217; (all exogenous). Equilibrium sorts workers into strongly and weakly bundled tasks, and inactivity, depending on their abilities and the value of their outside option.</p><p>We can also model P as an inverse demand function, P(Y) = Y^(-1/&#946;) for &#946;&gt;0, so demand in the goods market is downward sloping and convex. Substitution effects are also now endogenous by substituting in P(Y) for P in U&#8217;/P. Solve for the equilibrium, and employment falls only if:</p><p>(1/&#946;)(dlnY/dm) &gt; &#945;dln(&#956;2(m))/dm.</p><p>Employment falls when the output gains from frontier capability advancements exceed the productivity gains from automation, weighted by their elasticities. <em>If goods demand is more inelastic</em>, we will observe <em>greater disemployment effects</em> (and AI reducing employment is more likely), and <em>if the output share of task one is greater</em>, we will see <em>lower disemployment effects</em> (and employment falls less likely). The intuition is that more inelastic demand means that sales are less responsive to prices, so all other things equal profits adjust more rapidly. The AI productivity shock reduces prices and profits to the extent that firms cut back on hiring. If the output share of task one is greater, then less workers are in weakly bundled occupations. </p><p>Our overall conclusion is that the extent to which AI is labour-augmenting or a direct substitute to labour inputs will determine the employment effects. In all competitive equilibria (unique but changes according to the parameter changes), the number of both weakly and strongly bundled occupations is nonzero however. </p><p>Nonetheless, <em>(rapidly) increasing frontier capability is sufficient for more roles to be at risk of automation</em>. This does NOT require a singularity nor superintelligence. As m rises, s*1 rises too. If this model broadly holds, then the risk of large disemployment effects within the near future is high, especially given current forecasts on the advent of AGI. Organised rent-seeking and regulatory capture can delay this via raising c, yet output growth will also be lower. I would rather redistribute via fiscal policy (automatic stabilisers) and taxes/transfers than via predistribution, perhaps via UBI or NIT, <a href="https://open.substack.com/pub/microfounded/p/why-we-must-contemplate-life-in-a?utm_source=share&amp;utm_medium=android&amp;r=56swa">yet some policy response will likely be required</a> to cushion the shock.<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-6" href="#footnote-6" target="_self">6</a></p><div class="captioned-button-wrap" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/p/ai-employment-effects-a-primer?utm_source=substack&utm_medium=email&utm_content=share&action=share&quot;,&quot;text&quot;:&quot;Share&quot;}" data-component-name="CaptionedButtonToDOM"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! This post is public so feel free to share it.</p></div><p class="button-wrapper" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/p/ai-employment-effects-a-primer?utm_source=substack&utm_medium=email&utm_content=share&action=share&quot;,&quot;text&quot;:&quot;Share&quot;}" data-component-name="ButtonCreateButton"><a class="button primary" href="https://www.ciaranmarshall.co.uk/p/ai-employment-effects-a-primer?utm_source=substack&utm_medium=email&utm_content=share&action=share"><span>Share</span></a></p></div><p><strong>O-ring technology</strong></p><p>An alternative yet related approach by <a href="https://www.nber.org/system/files/working_papers/w34639/w34639.pdf">Joshua Gans (2026)</a> generalises this task-based framework, yet departs from Garicano et al in abandoning Cobb-Douglas assumptions. There are no diminishing returns to tasks as inputs - following the logic of learning-by-doing endogenous growth models. Spillovers between tasks generate complementarities, which roughly offset diminishing marginal returns. Hence the implications for wages and employment are more optimistic.</p><p>Hence production is a simple multiplicative function of all the tasks required. Jobs are not represented as bundles, but rather final output itself is decomposed into n tasks. A representative household supplies L hours given a fixed time constraint, so for tasks performed via human labour, q=aL where a is labour productivity. Each task can also be automated by technology &#952; at cost r. If a task is automated, q=&#952;.</p><p>As output is simply multiplicative and there exists constant returns to scale, changes to labour supply scale the entire production function. Therefore wages are determined by Nash bargaining rather than marginal product (in line with DMP models). Moreover, if not all tasks can be automated, then labour is still required as an input. Under these conditions, total wage costs W(a) are set to maximise the following surplus, with a being the number of tasks able to be automated:</p><p>[{W(a)-u0}^&#946;][{Y(a)-r-W(a)}^(1-&#946;)]</p><p>where u0 is the outside option, the payoff from disagreement. This gives the following result:</p><p>W*(a) = u0+&#946;(Y(a)-r-u0).</p><p>In other words, a solution very similar to a <a href="https://open.substack.com/pub/microfounded/p/search-and-matching-under-the-ai?utm_source=share&amp;utm_medium=android&amp;r=56swa">DMP model</a><a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-7" href="#footnote-7" target="_self">7</a>. </p><p>Profits are given by &#928;(a) = (1-&#946;)(Y(a)-r-u0) by substituting W*(a) into our definition. An agreement is not reached only if all tasks can be automated. However this more optimistic result ignores heterogeneity and perhaps make unrealistic assumptions regarding scale effects and complementarities. Therefore one should see this model as a description of jobs and production where technology and labour complement each other, which produces similar results to the strongly bundled case.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-1" href="#footnote-anchor-1" class="footnote-number" contenteditable="false" target="_self">1</a><div class="footnote-content"><p>There also exists organisational constraints within and across firms and industries that delay adoption and diffusion; another Coasian point. Conversely, some industries face more rapid and instantaneous spillovers and agglomeration effects than others. For now, let&#8217;s abstract from this and focus on the within-job dynamics.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-2" href="#footnote-anchor-2" class="footnote-number" contenteditable="false" target="_self">2</a><div class="footnote-content"><p>When c falls, the fixed costs to starting a new firm will also fall, albeit this is outside the scope of the model. Firms will shrink as Coasian coordination costs fall. More households will operate their own businesses, so the capital share of output surges.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-3" href="#footnote-anchor-3" class="footnote-number" contenteditable="false" target="_self">3</a><div class="footnote-content"><p>For me, this involves blogging, and providing a unique commentary distinct from what you might get from an LLM. Unique is the key word here, which is why I think the concerns in academia are unwarranted: AI is augmenting innovation thus far, albeit some fields such as mathematics may be more exposed to substitution. I&#8217;m also currently developing a career in manufacturing sectors where human labour will still always be an essential task input. The best jobs in these industries involve a range of data analysis (to model KPI and inventory dynamics etc) and social coordination (i.e. &#8216;bundled&#8217; management roles), or oversee automated inputs (a prime example being CNC and other roles in precision manufacturing). In both these cases, AI is complementary and labour-augmenting. In my view, the traditional prestigious professions (coding, law, IB, consulting, etc) will suffer the greatest relative decline.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-4" href="#footnote-anchor-4" class="footnote-number" contenteditable="false" target="_self">4</a><div class="footnote-content"><p>We're abstracting from information frictions so there&#8217;s no moral hazard. Wages depend on output, as is standard in perfect competition. Hence utility maximisation is output maximisation. If you insist on incorporating these dynamics, then my priors are that raising c is sufficient here, so the overall dynamics are the same. Departing from perfect competition largely introduces a markdown, yet otherwise the optimisation problem is the same. In a minute we will model this explictly. A more interesting question is how AI affects our tradeoffs between consumption and leisure, hence the income and substitution effects for labour supply. The paper introduces outside options later. I&#8217;m blogging as I'm reading, so we'll find out later. Intertemporal decisions between consumption vs saving also feature though, especially as AI will affect r. I also wonder how workers will reallocate into bundled roles, which will require modelling the tradeoff between consumption, leisure, and human capital investment. </p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-5" href="#footnote-anchor-5" class="footnote-number" contenteditable="false" target="_self">5</a><div class="footnote-content"><p>If you're an undergraduate new to economics, or seek to refresh your memory, the proof in the paper is easy to follow. Only basic multivariate calculus and a cursory familiarity with Lagrangians is necessary. On a general note, my post covers the intuition in my own reasoning, so readers should go to the paper for the proofs.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-6" href="#footnote-anchor-6" class="footnote-number" contenteditable="false" target="_self">6</a><div class="footnote-content"><p>In some cases the HANK literature implies that redistribution can actually be efficient, so a social planner doesn't necessarily choose between efficiency vs equity according to their social welfare function. A subsequent post will cover this in more detail.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-7" href="#footnote-anchor-7" class="footnote-number" contenteditable="false" target="_self">7</a><div class="footnote-content"><p>Note that my conclusions in this back of the envelope exercise also mirror the Garicano et al result, in a case where AI is labour-augmenting for many roles (this was written before Claude Code, Moltbook, and Mythos).</p></div></div>]]></content:encoded></item><item><title><![CDATA[May 2026 links]]></title><description><![CDATA[I'm going back to a monthly format for these, as with my conversion to writing on the browser version, I can now make multiple drafts.]]></description><link>https://www.ciaranmarshall.co.uk/p/may-2026-links</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/may-2026-links</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Fri, 01 May 2026 14:33:01 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p>I'm going back to a monthly format for these, as with my conversion to writing on the browser version, I can now make multiple drafts.</p><ol><li><p><a href="https://x.com/i/status/2049330123464393084">But I thought smart kids turn out to be lonely recluses...</a></p></li><li><p><a href="https://x.com/i/status/2047444621064605936">AGI is coming</a>. If anything I revise my expected date for when it will arrive to late 2026.</p></li><li><p><a href="https://x.com/i/status/2049854314680652161">Barleycorn chess.</a></p></li><li><p>On the other hand many claim <a href="https://x.com/i/status/2049462825966268908">this</a> is a bullish signal for AI progress&#8230;</p></li><li><p>Arguably worse than the Great Leap Forward, which would hence place <a href="https://x.com/i/status/2049407118529151144">this</a> policy as amongst the most evil ever in history.</p></li><li><p>Moral hazard: AI <a href="https://x.com/i/status/2049650978517885146">and studying</a> edition?</p></li><li><p>An <a href="https://x.com/i/status/2049475900001955951">underrated yet important</a> point.</p></li><li><p><a href="https://x.com/i/status/2049267428795064345">Yes</a>. Adoption is not instant given the social coordination dynamics within a firm. Think Coasian!</p></li><li><p><a href="https://x.com/i/status/2049613412561277161">Is sychophancy actually a feature of alignment training?</a></p></li><li><p><a href="https://x.com/i/status/2046680114801660181">This</a> presumably limits the economic fallout from the Iran shock?</p></li><li><p><a href="https://x.com/i/status/2046988031165382669">Congestion pricing</a> goes to court?</p></li><li><p><a href="https://x.com/i/status/2046024739181781462">A vaccine for pancreatic cancer?</a> AI delivers live-saving biotechnologies as well as potentially bioweapons. We survived Covid and worse pandemics, then prospered, so humanity will survive an AI-generated pandemic if such actually occurs.</p></li><li><p>Today's good news: the end of <a href="https://x.com/i/status/2045757539409621414">Guinea worm.</a></p></li><li><p><a href="https://www.aeaweb.org/articles?id=10.1257/aer.20231696&amp;from=f">"Arrests made near the end of an officer's shift typically require overtime work, and officers respond by reducing arrest frequency but increasing arrest quality. Days in which an officer works a second job after their police shift have higher opportunity cost, also reducing late-shift arrests."</a></p></li><li><p>Much of the decline in L share of Y can be explained via digital platforms compensating our data production with access. In particular, "the marginal utility of interface time can be non-decreasing". <a href="https://zenodo.org/records/19544419">GDP understates the welfare gains of the internet.</a></p></li><li><p><a href="https://www.app.vistadex.com/claim-markets">A prediction market for pundits.</a> Glad to see that those I follow are performing well.</p></li><li><p>I think it's the level of granular detail involved that makes <a href="https://marginalrevolution.com/marginalrevolution/2026/04/the-raphael-show-at-the-nyc-met.html">Raphael</a> stand out, and why renaissance art in general is popular. This lends credence to theories of aesthetics emphasising the role of creative skill? Likewise, the controversy that <a href="https://marginalrevolution.com/marginalrevolution/2026/04/the-marcel-duchamp-show-at-moma.html">Duchamp</a> generates downgrades theories of art as necessarily encoding social statements? Art isn't activism; beauty exists independent of such? (Picabia is one of the most talented I've seen though - it doesn't come close!)</p></li><li><p>A paper leaning towards our natural adaptation processes at the cellular level being the primary explanation for drug resistance, <a href="https://t.co/N2ptdAIkwt">as opposed to mutation.</a></p></li></ol><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div>]]></content:encoded></item><item><title><![CDATA[Should Mythos be made public?]]></title><description><![CDATA[Why Anthropic is correct in making its bold move to restrict its latest rollout]]></description><link>https://www.ciaranmarshall.co.uk/p/should-mythos-be-made-public</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/should-mythos-be-made-public</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Thu, 30 Apr 2026 15:21:41 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p>Contrary to the prevailing media narrative, Mythos is not a model produced specifically for cybersecurity tasks. Like Claude or ChatGPT, it is another SOTA frontier model. Its delayed and restricted rollout is entirely a function of Anthropic's heavy focus on alignment. This model <a href="https://open.substack.com/pub/peterwildeford/p/mythos-is-just-the-beginning?utm_source=share&amp;utm_medium=android&amp;r=56swa">identified vulnerabilities</a> in every website, so in theory could be open to abuse by malicious actors. Hence, the restricted rollout.</p><p>More of these frontier LLMs with similar capabilities will soon be produced by ChatGPT and Google, if they have not already done so. Arguably ChatGPT 5.5 is comparable to Mythos. Are these companies as concerned with cybersecurity risk? Or do they consider their current guardrails, and predominant cybersecurity practices<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-1" href="#footnote-1" target="_self">1</a> amongst firms, to be sufficient to mitigate the risks at hand?</p><p>My overarching point is that the degree to which models pose a cybersecurity risk is somewhat arbitrarily defined by the lab itself. This implicit alignment regulatory system operates entirely voluntarily and on self-reporting. Yes the US government operates some leverage and influence over Anthropic on this, yet aside from designating supply chain risks, the government has yet to enact executive or legislative action. Therefore, OpenAI and Google can easily arrive at a different conclusion.</p><p>Does Anthropic's heavy focus on alignment risks and its EA ethos place it at a disadvantage? Is it rational for Open AI and Google to release their Mythos-class models once they arrive, or should they follow Anthropic's path? What is the equilibrium here? Is this optimal? What are the existential risk implications?</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><p><strong>Why public choice favours Anthropic, and why this is good for society</strong></p><p>My first thought is that coordination across the companies breaks down - adversely impacting <a href="https://open.substack.com/pub/microfounded/p/why-we-must-contemplate-life-in-a?utm_source=share&amp;utm_medium=android&amp;r=56swa">the exact multi-agent institutional governance</a> we need.</p><p>In the short-run, Anthropic is at a clear disadvantage in maximising market share and volume, which substantially affects its bottom line. However, this equilibrium holds only for as long as deviation by the competitors is not punished. Anthropic hence yields an incentive to penalise Mythos-class releases via any means it can.</p><p>An obvious high-return example of such a scenario is via lobbying. Anthropic, alongside the wider EA community, seems to me are clearly yet subtly investing substantially in their influence amongst lobbyists in Washington, political campaigns, the think-tank world, and the wider media. They will then likely argue for governments favouring &#8220;more responsible&#8221; actors, more statutory regulation of AI companies, and even restrictions on the capabilities of each new model release. </p><p>Moreover, if a disastrous tail-risk event does occur with a more lenient release plan, then the more cautious party stands to benefit. So much is contingent on their respective probabilities of existential risk scenarios? Prediction markets and the superforecasting industries will benefit, and in my view AI researchers and economists<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-2" href="#footnote-2" target="_self">2</a> will prevail over both the hardcore accelerationists and the doomers, who are becoming increasingly luddite in their opposition to data centres. </p><p>On the margin, this grants more of an advantage to Anthropic, conditional on increased political influence. I will be following (and writing about) these developments closely within the next few years. AI will feature as an increasingly salient entity in mainstream political discourse in the years ahead. Given that caution untimately yields positive externalities in terms of limiting the influence of a nascent pause agenda, backed by anti-abundance and degrowther types on the left, this equilibrium is also the socially optimal outcome.</p><p>This voluntary regulatory institution operating on self-restraint is preferable for all firms to following government mandates, and its wider political implications. Therefore, Open AI and Google will also restrict their initial releases of their Mythos-tier plans.</p><p>Governments, coordinating globally, will likely create statutory bodies to enforce evaluation standards and alignment priorities. Some will set extensive disclosure and reporting obligations for some functions, as is already the case in the EU. UK AI regulation is surprisingly lax, yet expect it to get stringent. Alongside the Online Safety Act, the left-leaning parties will successfully legislate for mandatory disclosure requirements: both for safety concerns and perhaps to improve damaged economic ties to the EU. Where protectionism plays a more powerful political force, in the United States and China, export and import controls will be tightened. Open source models will diminish in clout. All of this is far preferable to an outright pause on all further AI development, or even bans.</p><p>UPDATE (30/04/2026):</p><p><a href="https://x.com/i/status/2049884275495895352">It appears that</a> <a href="https://x.com/i/status/2049854151283093546">ChatGPT 5.5 already matches</a> the capabilities of Mythos. However, increasingly <a href="https://x.com/i/status/2049712078836170843">the definition of a frontier model is rapidly changing</a>, which validates this prediction of a tiered market. <a href="https://x.com/i/status/2049840502107697364">We are also seeing the implied implications for public regulation</a>.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-1" href="#footnote-anchor-1" class="footnote-number" contenteditable="false" target="_self">1</a><div class="footnote-content"><p>Primarily via building multi-layered systems so an entire exploit chain is required to compromise the website; also the standard PIN codes, passwords, biometrics, encryption, and the like.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-2" href="#footnote-anchor-2" class="footnote-number" contenteditable="false" target="_self">2</a><div class="footnote-content"><p>Whom as I have argued in my last piece, have the most accurate probabilities in my view.</p></div></div>]]></content:encoded></item><item><title><![CDATA[A few musings on life in a post-AGI world]]></title><description><![CDATA[Plus why healthy epistemic reasoning habits are penalised to the detriment of society]]></description><link>https://www.ciaranmarshall.co.uk/p/why-we-must-contemplate-life-in-a</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/why-we-must-contemplate-life-in-a</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Tue, 21 Apr 2026 18:16:27 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!j4nj!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fb5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p>Here are <a href="https://x.com/i/status/2045581412598947957">my initial priors</a>, posted on X, on how labour markets will change in a post-AGI world:</p><blockquote><p>&#8220;Moravec's paradox means manual labour and trades are less likely to be automated. Jobs on alignment, prompting, those relating to empathy and creativity, will likely increase in number and wages.</p><p>If L share of Y falls, &#916;^2Y&gt;0 so K share rises. AI (agents) reduce fixed costs to launching startups too. In worst-case scenario where AGI automates most jobs, I expect a lot more entrepeneurs, and a decline in firms. Firms arise given inefficiencies as Coase proved, so the result pushes us closer to the Pareto frontier even if not cost-free. Those are my priors of life in the worst-case scenario.</p><p>Far more likely, humans maintain a comparative advantage in many occupations, low substitutability between tasks mean human L is still required, and new occupation classes arise. On my second point, worth noting that AI can complement rather than substitute many roles. </p><p>Entry-level jobs will erode however, so this increases intergenerational inequality, yielding political economy implications. Young adults are already turning to the radical left in Britain. Hopefully YIMBY increases in popularity as the concerns of younger generations gain more traction.&#8221;</p></blockquote><p><a href="https://x.com/i/status/2044808883928186936">AI researchers and those working at the top AI labs seem to agree</a>. AGI is arriving faster than we think, and is arguably already here with Mythos, which would explain its restricted rollout. I place <em>the odds of widespread AGI commerically available from 2030 at roughly 60%</em>. </p><p>The bottlenecks arise in alignment issues favouring caution in implementation and rollout, currently alongside <a href="https://x.com/i/status/2041253263597527445">a number of complementarities</a> in senior roles. Yet we must increasingly contemplate a world in which these bottlenecks dissappear. Entire professions, many of them prestigious (such as law, programming, IB, etc), will be eliminated and present status hierarchies re-written. Those with conventional career paths will lose out relative to outsider nonconformists or those with more turbulent histories. Raw IQ, at least that proportion orthogonal to established social networks, will matter more in hiring in a world where AI can estimate our cognitive ability via our social media output alone. Therefore it's plausible that equality in opportunity, and intergenerational social mobility, will increase. As with all technological revolutions, there will be winners and losers (at least in relative terms), with those disproportionately at the top of existing hierarchies losing relative to the more disasvantaged. Ultimately, the result will be a more meritocratic and efficient world.</p><p>Alignment is a vital issue, and I agree with S&#233;b Krier et al that it's an institutional and incentive problem, which is where I depart from most of the EA and rationalist community. With clever prompting, one can get an LLM or agent to deviate from their alignment training. <em>My p(doom) has now increased </em>from the sub 1% superforecaster average <em>to 5-6%</em>, close to the median for AI researchers. Although I'm not a doomer, it's increasingly apparent that many of the Yudkowsky and LessWrong predictions are materialising, which strengthens the hypothesis they're correct. </p><p>To perhaps add some clarity, my p(doom)=(5%,6%) means it's a non-negligible possibility yet otherwise a worst-case scenario. Such probabilities could have held for numerous technological advancements and military events throughout human history too - arguably we've faced far worse XR odds before. Therefore my immense AI optimism remains. Anything less still strikes me <a href="https://x.com/i/status/2045506803216343190">as somewhat vulgur</a>. Yet AI alignment is by far our most pressing economic, social, and political issue, and it's not even close! Conventional partisan and ideological alignments seem wholly outdated for the nascent revolution that is materialising.</p><p>P(doom) is perhaps less anchored to base rates than other forecasting questions. I have drawn upon a range of economic models, and priors well-informed from a history of structural cultural and technological changes, in order to arrive at a reasonable point estimate. A weakness of my writing is that I often don't state my probabilities or bet according to such (although prediction markets aren't legalised in Britain). I'll make more effort to do so going forward.</p><p>However, aside from <a href="https://chatgpt.com/share/69e7bc6a-0204-8393-ab2b-29aa79d375e9">an endogenous bias vs variance tradeoff in our objective functions</a>, the penalties for attempting a precise and well-calibrated probabilistic forecast that never materialised seem worse than falsified yet vague and verbose punditry. Robin Hanson got dunked on <a href="https://x.com/i/status/2046588299230228875">for this</a> today. What strikes me as impressive however is that Tyler and Hanson were onto the possibility of AI's upcoming rapid development to AGI back when most considered such limited to the realm of esoteric science fiction.</p><p>More generally, the implicit social penalty on inaccurate forecasts penalises prediction and updating based on well-calibrated likelihoods. This generates substantial negative externalities for the quality of our discourse. Prediction markets are socially valuable precisely because they generate the opposite incentives. Anyone taking the first (and courageous) step to quantify their point estimates with precise numbers and ranges deserves credit. I think the defining legacy of the emergence of the LessWrong rationalist crowd, is the idea that an army of autistic autodidacts can achieve the same epistemic status and legitimacy of established domain experts. Perhaps with a pinch of grandiosity, I label this the triumph of Bayesian epistemology. A post-AGI world might sharpen the returns on healthy epistemic habits relative to conventional credentialised paths?</p><p>UPDATE (23/04/2026): I have just noticed this pop up on my X feed.</p><div class="captioned-image-container"><figure><a class="image-link image2 is-viewable-img" target="_blank" href="https://substackcdn.com/image/fetch/$s_!j4nj!,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fb5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg" data-component-name="Image2ToDOM"><div class="image2-inset"><picture><source type="image/webp" srcset="https://substackcdn.com/image/fetch/$s_!j4nj!,w_424,c_limit,f_webp,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fb5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg 424w, https://substackcdn.com/image/fetch/$s_!j4nj!,w_848,c_limit,f_webp,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fb5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg 848w, https://substackcdn.com/image/fetch/$s_!j4nj!,w_1272,c_limit,f_webp,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fb5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg 1272w, https://substackcdn.com/image/fetch/$s_!j4nj!,w_1456,c_limit,f_webp,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fb5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg 1456w" sizes="100vw"><img src="https://substackcdn.com/image/fetch/$s_!j4nj!,w_1456,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fb5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg" width="1080" height="2340" data-attrs="{&quot;src&quot;:&quot;https://substack-post-media.s3.amazonaws.com/public/images/b5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg&quot;,&quot;srcNoWatermark&quot;:null,&quot;fullscreen&quot;:null,&quot;imageSize&quot;:null,&quot;height&quot;:2340,&quot;width&quot;:1080,&quot;resizeWidth&quot;:null,&quot;bytes&quot;:556163,&quot;alt&quot;:null,&quot;title&quot;:null,&quot;type&quot;:&quot;image/jpeg&quot;,&quot;href&quot;:null,&quot;belowTheFold&quot;:true,&quot;topImage&quot;:false,&quot;internalRedirect&quot;:&quot;https://www.ciaranmarshall.co.uk/i/194948408?img=https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fb5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg&quot;,&quot;isProcessing&quot;:false,&quot;align&quot;:null,&quot;offset&quot;:false}" class="sizing-normal" alt="" srcset="https://substackcdn.com/image/fetch/$s_!j4nj!,w_424,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fb5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg 424w, https://substackcdn.com/image/fetch/$s_!j4nj!,w_848,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fb5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg 848w, https://substackcdn.com/image/fetch/$s_!j4nj!,w_1272,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fb5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg 1272w, https://substackcdn.com/image/fetch/$s_!j4nj!,w_1456,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2Fb5528140-c0ab-4563-b323-f009d20044a5_1080x2340.jpeg 1456w" sizes="100vw" loading="lazy"></picture><div class="image-link-expand"><div class="pencraft pc-display-flex pc-gap-8 pc-reset"><button tabindex="0" type="button" class="pencraft pc-reset pencraft icon-container restack-image"><svg role="img" width="20" height="20" viewBox="0 0 20 20" fill="none" stroke-width="1.5" stroke="var(--color-fg-primary)" stroke-linecap="round" stroke-linejoin="round" xmlns="http://www.w3.org/2000/svg"><g><title></title><path d="M2.53001 7.81595C3.49179 4.73911 6.43281 2.5 9.91173 2.5C13.1684 2.5 15.9537 4.46214 17.0852 7.23684L17.6179 8.67647M17.6179 8.67647L18.5002 4.26471M17.6179 8.67647L13.6473 6.91176M17.4995 12.1841C16.5378 15.2609 13.5967 17.5 10.1178 17.5C6.86118 17.5 4.07589 15.5379 2.94432 12.7632L2.41165 11.3235M2.41165 11.3235L1.5293 15.7353M2.41165 11.3235L6.38224 13.0882"></path></g></svg></button><button tabindex="0" type="button" class="pencraft pc-reset pencraft icon-container view-image"><svg xmlns="http://www.w3.org/2000/svg" width="20" height="20" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2" stroke-linecap="round" stroke-linejoin="round" class="lucide lucide-maximize2 lucide-maximize-2"><polyline points="15 3 21 3 21 9"></polyline><polyline points="9 21 3 21 3 15"></polyline><line x1="21" x2="14" y1="3" y2="10"></line><line x1="3" x2="10" y1="21" y2="14"></line></svg></button></div></div></div></a></figure></div><p>If this venture pulls through, then this obviously yields implications for Imas&#8217; relational sector model, and my priors on the extent to which Moravec's paradox acts as a constraint to AI capabilities. Suddenly, the likelihood of mass unemployment has surged. I now place this at roughly 5%, so for the first time ever I consider this a real possibility, rather than a hypothetical relegated to the land of science fantasties. </p><p>Note that even if the aggregate effect throughout time is that, eventually, more jobs are created via AI-induced economic growth than lost (as with past structural transitions), there can still be adverse short-run implications. The possibility of AGI (and perhaps ASI!) is nascent, whilst I don&#8217;t see much of these new jobs arriving anytime soon! This is most likely the reason for the deterioration in the entry-level market affecting graduate entry into the labour market, whilst other US economic indicators seem stable and within trend. Nonetheless, economists&#8217; priors and predictions are far too anchored to past technological changes, whilst it is plausible that this time could indeed be different!</p><p>Conditional on AI-induced mass unemployment, we will need UBI, or some fiscal policy response, in order to alleviate the inevitable unrest. In such a world, output surges, so this becomes affordable. Even most autocracies are constrained via the possibility of riots, and change policy or personnel based on these! Arguably the welfare state arose in the first place to ease and soften the transition throughout the Industrial Revolution, with its post-war expansion occuring whilst we transitioned from manufacturing to services. So I no longer consider traditional minarchist libertarianism as adequate to address the scale of the challenges we face today, although nonetheless I still subscribe to a soft libertarianism.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><p></p>]]></content:encoded></item><item><title><![CDATA[Mid-April 2026 links]]></title><description><![CDATA[If only Carlsen was still defending his title. That match would be the game of the century.]]></description><link>https://www.ciaranmarshall.co.uk/p/mid-april-2026-links</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/mid-april-2026-links</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Tue, 21 Apr 2026 17:00:58 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<ol><li><p><a href="https://x.com/i/status/2044403956235808818">If only Carlsen was still defending his title</a>. That match would be the game of the century.</p></li><li><p><a href="https://x.com/i/status/2043230135281971466">The extent to which animals form complex and intimate relationships</a> never ceases to amaze me. This should be a factor in your views on sentience and consciousness, and on the moral worth of animals in rights debates.</p></li><li><p><a href="https://x.com/i/status/2043833204759499068">How will this change</a>, now that the likelihood of cyber attacks on online payments and banking infrastructure is increasing?</p></li><li><p>On why r* is endogenous in HANK. "<a href="https://www.aeaweb.org/articles?id=10.1257/aer.20240642&amp;from=f">The Taylor principle is not sufficient to guarantee uniqueness of equilibrium in HANK if risk is even mildly countercyclical: multiple bounded-equilibria exist</a>". The mainstream addressed the Cambridge capital controversies long ago.</p></li><li><p>I can't help but notice that this is a neglected <a href="https://psycnet.apa.org/record/2026-12320-001">yet important alignment issue</a>.</p></li><li><p>Leftist voters and more educated voters prioritise <a href="https://academic.oup.com/qje/advance-article-abstract/doi/10.1093/qje/qjag019/8571578?redirectedFrom=fulltext">redistribution over predistribution</a>, and the latter is the case for GOP and less educated voters.</p></li><li><p><a href="https://www.aeaweb.org/articles?id=10.1257/aer.20241465">Emigration benefits the home country via increased investment into human capital</a>. Given the importance of human capital and <a href="https://open.substack.com/pub/microfounded/p/what-abundance-and-open-borders-supporters?utm_source=share&amp;utm_medium=android&amp;r=56swa">the still large role that environment features</a> in explaining trait variance, and the role of networks in allocating talent, I'm turning against the idea of college education as mostly signalling.</p></li><li><p>Declining search costs are assisting us in <a href="https://x.com/i/status/2040098098819592659">overcoming availability bias</a>, and increasing the utility of Bayesian reasoning over mispecified heuristics? Under a rational inattention framework with time constraints, and endogenous search costs to information acquisition (reducing over time with the internet and social media then AI), <a href="https://open.substack.com/pub/microfounded/p/yes-partisan-bias-in-forecasting?utm_source=share&amp;utm_medium=android&amp;r=56swa">the link is clear</a>. If the latter holds, then <a href="https://x.com/i/status/2040112708821959169">this model is also mispecified</a>, and rational expectations becomes a more attractive prior.</p></li></ol><p></p>]]></content:encoded></item><item><title><![CDATA[Why I don't replicate papers]]></title><description><![CDATA[Facing a rather stringent time constraint, I tend to just adjust via downgrading my confidence in any paper posted on X instead.]]></description><link>https://www.ciaranmarshall.co.uk/p/why-i-dont-replicate-papers</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/why-i-dont-replicate-papers</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Sat, 18 Apr 2026 21:50:45 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p>Facing a rather stringent time constraint, I tend to just adjust via downgrading my confidence in any paper posted on X instead. If such a paper attracts enough interest and engagement for someone to replicate, then it'll be scrutinised. I still retweet and post papers, as I assume my audience is statistically literate so aware a paper is not slam-dunk proof. However, in the age of Codex and autonomous Claude agents, is there still an excuse for my relative nonchalance and radical skepticism on the latest publishings? Here is (part of) my latest conversation with Chat:</p><p>Me - &#8220;Yeah my main issue with delegating replication to LLMs or AI agents is that they use different code/algorithms which produces heterogeneity in results. If I was to run a Callaway Sant'Anna DiD then Codex and Claude Code would disagree. Then they also disagree with how to enact robustness checks and run hypothesis testing. So a significant result from Codex could be null with a Claude AI agent. So unfortunately I still need to be in the loop, and allocate hours in my time constraint to do so.&#8221;</p><p>Chat - &#8220;Yeah&#8212;that&#8217;s a very real problem, and you&#8217;re not imagining it. What you&#8217;re running into is basically implementation variance masquerading as epistemic disagreement.</p><p>With something like Callaway&#8211;Sant&#8217;Anna DiD, small differences compound fast:</p><p>Estimator defaults (e.g., weighting schemes, cohort definitions, handling of unbalanced panels)</p><p>Treatment timing encoding (especially with staggered adoption)</p><p>Inference choices (bootstrap vs asymptotic, clustering level, number of reps)</p><p>Pre-trend handling / event study specification</p><p>Missing data / sample trimming rules</p><p>Two agents can both say &#8220;I ran CS DiD&#8221; and still be doing meaningfully different estimations. So when Codex gives you a significant ATT and Claude doesn&#8217;t, it&#8217;s often not &#8220;AI disagreement&#8221;&#8212;it&#8217;s model specification drift.</p><p>Your conclusion is basically right: you can&#8217;t fully outsource this without losing control of identification.</p><p>But you can reduce the time cost without giving up rigor if you treat LLMs less like &#8220;analysts&#8221; and more like strictly controlled executors. A few ways to tighten that:</p><p>1. Lock the spec, not just the method</p><p>Instead of saying &#8220;run Callaway&#8211;Sant&#8217;Anna,&#8221; define:</p><p>exact package (did in R, version if possible)</p><p>estimator (att_gt with specific args)</p><p>control group definition</p><p>clustering level</p><p>bootstrap reps</p><p>event window</p><p>Think of it like writing a pre-analysis plan for the AI.</p><p>2. Force identical pipelines across agents</p><p>Have both Codex and Claude:</p><p>use the same language (R vs Python differences matter here)</p><p>same package (don&#8217;t let one default to a custom implementation)</p><p>same seed, same bootstrap reps</p><p>If they still diverge after that, then it&#8217;s interesting.</p><p>3. Use them for robustness grids, not single estimates</p><p>Where they do shine:</p><p>&#8220;Run this spec across 10 reasonable variations&#8221;</p><p>Different clustering levels, sample restrictions, etc.</p><p>You&#8217;re not asking &#8220;what&#8217;s the answer?&#8221;</p><p>You&#8217;re asking &#8220;how fragile is the answer?&#8221;</p><p>4. Treat disagreement as a diagnostic</p><p>Instead of a nuisance, you can flip it:</p><p>If Codex &#8800; Claude &#8594; something in the pipeline is underspecified</p><p>That&#8217;s actually a pretty powerful specification stress test.</p><p>5. Keep yourself in the loop at the choke points</p><p>You don&#8217;t need to do everything manually&#8212;just:</p><p>define the estimand + identification strategy</p><p>verify one &#8220;canonical&#8221; run yourself</p><p>let agents handle extensions / formatting / robustness sweeps</p><p>What you&#8217;re resisting (fully delegating) is the right instinct. In empirical work, especially with causal inference, the last 10% of control over specification is doing 90% of the epistemic work.</p><p>So your current setup&#8212;LLMs as assistants, not authorities&#8212;is basically the equilibrium most serious people end up at.</p><p>If anything, the interesting meta-point is:</p><p>the fact that different agents give different answers is exactly why your kind of selective engagement on X works. Most people there won&#8217;t track these nuances, but you know where the bodies are buried.</p><p>Out of curiosity&#8212;are you mostly working in R for this, or bouncing between R/Python depending on what the agent outputs?&#8221;</p><p>Me - &#8220;I tend to default to R simply because that's what I was trained in at uni. I have a working knowledge of both Python and Stata too. R vs Stata is a rather contentious divide amongst economists, yet I'll simply use R until I hit a bottleneck then try the others.</p><p>I'm a macroeconomist (or was) though, so mostly deal with Dynare.&#8221;</p><p>Chat - &#8220;That makes sense&#8212;and honestly, your workflow sounds pretty sane for someone coming from macro into applied micro/empirical work.</p><p>R as the &#8220;home base&#8221; is a good choice here, especially for DiD-type work. The did package (Callaway&#8211;Sant&#8217;Anna) and related tooling are just more transparent than most Stata implementations, and you can actually see what&#8217;s going on under the hood when something looks off. Stata is often cleaner for quick replication, but it hides a lot of decisions unless you dig.</p><p>Your &#8220;R &#8594; hit bottleneck &#8594; switch&#8221; approach is basically what a lot of people converge to, even if they don&#8217;t admit it.</p><p>The Dynare angle is actually relevant here</p><p>Coming from Dynare/DSGE world, you&#8217;re used to:</p><p>tight control over model structure</p><p>clear mapping from assumptions &#8594; results</p><p>reproducibility being non-negotiable</p><p>That&#8217;s almost the opposite of modern applied micro, where:</p><p>identification is often fragile</p><p>implementation details matter a lot</p><p>and defaults quietly do heavy lifting</p><p>So your discomfort with LLM variability is basically your macro training kicking in:</p><p>&#8220;Why are there multiple answers to what should be a well-defined procedure?&#8221;</p><p>In DSGE, that would signal a bug.</p><p>In empirical micro, it&#8217;s Tuesday.</p><p>Where your background gives you an edge</p><p>You&#8217;re already thinking in a way that most people on X aren&#8217;t:</p><p>You notice specification sensitivity</p><p>You care about replicability across implementations</p><p>You&#8217;re aware of implicit assumptions baked into tools</p><p>That&#8217;s exactly the stuff that gets glossed over in a lot of the discourse you&#8217;re critiquing.</p><p>Practical way to reduce friction (without going full manual)</p><p>Given your stack (R + some Python/Stata + Dynare mindset), a pretty robust setup would be:</p><p>Canonical pipeline in R</p><p>did, fixest, maybe data.table</p><p>Strict function wrapper</p><p>Write one function that runs your exact DiD spec</p><p>All agents call that, not reinvent the wheel</p><p>Version locking</p><p>renv in R so results don&#8217;t drift over time</p><p>Cross-check layer (optional)</p><p>Occasionally replicate in Stata only as a sanity check, not as a primary workflow</p><p>That way, the LLMs can help generate code, but they&#8217;re plugging into your structure, not freelancing.&#8221;</p><p>Macroeconomists get far too much of a bad name for not importing the exact identification techniques of the micro credibility revolution. Yet increasingly, applied micro is learning from macro on the sensitivity of your estimates to different specification choices. The Goodman-Bacon result essentially reintroduced the salience of general equilibrium. Right down to the code, there always exist degrees of freedom.</p>]]></content:encoded></item><item><title><![CDATA[My stance on alcohol]]></title><description><![CDATA[We should reduce the social status of alcohol yet this does not imply abstention]]></description><link>https://www.ciaranmarshall.co.uk/p/my-stance-on-alcohol</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/my-stance-on-alcohol</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Fri, 17 Apr 2026 16:58:11 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p><a href="https://x.com/i/status/2043863307111575677">Bryan Johnson is yet again trending on X</a>, revelling in his usual notoriety. It appears that only taking the edge off a hard day at work with a pint of your son's blood, as opposed to a refreshing hoppy beverage in a bucolic pub, is acceptable to him&#8230;</p><p>Here is <a href="https://x.com/i/status/2044503613012381833">my response</a>, which (by my standards as someone in the early stages of developing as a public intellectual) was very popular:</p><blockquote><p>&#8220;I was once receptive to this claim that all alcohol is unhealthy, yet the "science" linking these transitory signal peaks to accelerated ageing is confounded and p-hacked to death. You control for recovering alcoholics, and the J-curve often still holds.</p><p>As for the MR studies used to demonstrate a causal linear relationship between alcohol consumption vs longevity, they introduce nonlinear proxies to get results for moderation specifically; eliminating the very randomisation we wanted in the first place. @cjsnowdon often makes this point. Here's my conversation with Chat for more on this topic: chatgpt.com/share/69dfe7d4&#8230;</p><p>Teetotalers are simply gaslighting you [1]. The threat to our social and public life from this nascent temperance movement is perhaps one of our greatest threats to happiness.&#8221;</p></blockquote><p>You can find the <a href="https://chatgpt.com/share/69dfe7d4-7554-8385-b5c1-5e4d6d906484">conversation with Chat here</a>. Regular readers know why I ultimately retracted my longevity series. The harms of alcohol were always disproportionately concentrated in heavier consumption patterns. Needless to say, I think that teetotalers also alienate the very individuals they need to convince to cut down or go abstinent. Absolutist and extremist statements like these give the longevity industry a bad name, which is a shame as ageing is one of life's greatest and most ubiquitous of tragedies and suffering, and to say <a href="https://silverlinings.bio/?chapter=present">it's socially costly</a> is an understatement.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><p>When I was physically dependent on alcohol, if I was told I must go abstinent forever, I wouldn't have been motivated to address my addiction. I now drink 5-11 drinks (14-30 units) a week and am healthier than ever. Moderation works well for me. Perhaps for most it fails, yet for a large subset <a href="https://www.google.com/url?sa=t&amp;source=web&amp;rct=j&amp;opi=89978449&amp;url=https://www.lesswrong.com/posts/CfX6pGepdjQYELSpK/alcoholics-anonymous-much-more-than-you-wanted-to-know&amp;ved=2ahUKEwjyopOx2fSTAxUia0EAHQTBDlcQFnoECCEQAQ&amp;usg=AOvVaw02gCDbz3ieJZ5HLm5aIInL">this strategy not only works</a> but is arguably most effective given the less strenuous lifestyle changes. This is indeed consistent with a process of <a href="https://open.substack.com/pub/microfounded/p/in-praise-of-hedonism?utm_source=share&amp;utm_medium=android&amp;r=56swa">rational addiction</a> <a href="https://open.substack.com/pub/microfounded/p/hedonists-embracing-virtue?utm_source=share&amp;utm_medium=android&amp;r=56swa">whereby preferences change</a> such that unstable consumption in equilibrium shifts to a stable steady-state over time.</p><p>However, I do agree with the notion that <em>we should reduce the status of alcohol</em>. <a href="https://open.substack.com/pub/thefitzwilliam/p/against-alcohol?utm_source=share&amp;utm_medium=android&amp;r=56swa">Numerous arguments</a> <a href="https://open.substack.com/pub/andymasley/p/alcohol-is-so-bad-for-society-that?utm_source=share&amp;utm_medium=android&amp;r=56swa">have been made</a> <a href="https://www.google.com/url?sa=t&amp;source=web&amp;rct=j&amp;opi=89978449&amp;url=https://marginalrevolution.com/marginalrevolution/2013/04/the-culture-of-guns-the-culture-of-alcohol.html&amp;ved=2ahUKEwjY-ofqh_WTAxURVUEAHRehMmwQFnoECB4QAQ&amp;usg=AOvVaw0nwng7ZfSmsq9vIPTDjQDE">against our drinking culture</a> [2], and one can broadly summarise them via these 12 points (I also offer my counterarguments to stimulate the discussion):</p><ol><li><p><em>Crime externalities</em>. By some estimates (you can type in &#8220;alcohol&#8221; into the Marginal Revolution search function too), drunkenness is implicated in half of violent crimes. However antisocial drunks tend to be antisocial individuals which introduces some endogeneity via selection, and if you subscribe to heritability estimates north of 50% for most traits, then this isn't an issue easily fixed without decapitation or stark disincentives to crime. Nonetheless it's fair to say that being drunk does impair inhibition and decision making, which leads to my next point.</p></li><li><p><em>Cognition</em>. Yes being drunk does make you stupider. This is prima facie common knowledge. Far more contentious is whether moderation impairs cognition, and there's yet to be reliable evidence of a linear relationship between cognitive decline in IQ vs alcohol consumption. My priors are that to the extent there is a linear relationship, alcohol likely impairs the frontal lobe (important for impulsivity and resisting temptation) and the amygdala first: consistent with increasing marginal utilities (certainly an abnormality!) under rational addiction. Anecdotally my cognition did not reflect <a href="https://x.com/i/status/2044431935049486425">my IQ</a> when I was undergoing active addiction.</p></li><li><p><em>Health</em>. Whilst I've just argued against a linear relationship, <a href="https://open.substack.com/pub/microfounded/p/links-for-mid-january-2026?utm_source=share&amp;utm_medium=android&amp;r=56swa">the effects of heavy drinking are stark</a>. Cancer, liver disease, dementia, heart disease - these are just some of the chronic illness that heavy alcohol consumption is implicated in. Whilst we lack strict causal evidence for the link (except for cancer where acetaldehyde is a known carcinogen), this thesis isn't contested. Gout, death by asphyxiation, alcohol poisoning, accidents, brain and abdominal haemorrhages, Wernicke's, physical dependency, liver cirrhosis, blackouts, one-punch murders - these are just the implications of hard drinking that I can list off the top of my head! Mortality is higher when one accounts for suicide too, and my focus on the tangible and measurable physical health effects ignores the mental health costs, so in fact understates the tail risks.</p></li><li><p><em>Discounting</em>. I've argued previously <a href="https://open.substack.com/pub/microfounded/p/in-defence-of-a-positive-discount?utm_source=share&amp;utm_medium=android&amp;r=56swa">in favour of nonzero discounting</a>, yet reducing your discount rate is one of the best means you can improve your life outcomes, and I can attest! Think of it as analogous to the returns to investing. It's not cost-free however, as the credibility of commitments demonstrates, so more virtuous lives must satisfy IC constraints to be feasible. This broadly constrains the extent to which abstinence as a norm is possible (at least in the West: in cultures that revolve around religious or kin-based social institutions, teetotalism does in fact <a href="https://en.wikipedia.org/wiki/Teetotalism">seem to be the norm</a>). Regardless, human capital determines lifetime wealth even in the Becker and Murphy model, so the more you can invest in this (and the less in costly substitutes given fixed time constraints) the better.</p></li><li><p><em>Embarrassment and hangovers</em>. I needn't say more. An underrated benefit of moderation for me is that my credibility and reputation as a public intellectual has markedly improved: my former anonymous X account was a stain on my legacy. 4) and 5) in particular are why I'm always open to the idea of future sobriety, so I guess I'm still sober curious.</p></li><li><p><em>Markups</em>. Booze cross subsidises hospitality and entertainment. A key argument in favour of our drinking culture yet drinkers pay a steep tax on eating out [3], and I like my meals too! Teetotalers that enjoy abstinence, rather than self-forcing themselves away [4], benefit from being free-riders.</p></li><li><p><em>Peer effects and spillovers</em>. Although you cannot live in a free society that values individual responsibility if all decisions are made appealing to the lowest common denominator (which is where Masley's argument, and EA more broadly, is especially weak), there are valid distributional concerns regarding the centrality of alcohol to our social lives.</p></li><li><p><em>Suboptimal information aggregation</em>. Tyler Cowen makes <a href="https://youtu.be/wPJo15XpvrE?si=EdNb9SItIQM8eUe-">this prescient observation</a>, which undermines the claim that drinking is necessary for socialisation. I suspect social anxiety, as a transaction cost to socialisation and matching, is more salient than he thinks. After a few rounds, I've noticed a tendency for conversations to descend into debates, where the usual tribal and signalling incentives hamper Aumann-style convergence to the optimal posterior.</p></li><li><p>One's <em>lifetime probability of addiction</em>, which is the most compelling reason to avoid drinking in my view. Alcohol use disorder affects roughly 1/10 British adults (according to Gemini). <a href="https://www.drinkaware.co.uk/research/alcohol-facts-and-data/alcohol-consumption-uk#:~:text=2011%20to%202022.-,Click%20here:%20England%20Wales%20Scotland%20Northern%20Ireland,(21%25%20vs%205%25).">As 1/5 are teetotal</a>, this gives a conditional probability of 1/8. For men, non-Muslims, and those not in Gen Z (where teetotalism is rapidly gaining in status), the risk is higher. Almost 1/3 men exceed the recommended limit of 14 units per week (admittedly myself included), so if you regularly binge drink on a weekend, your conditional probability can rise to almost 1/3. Simply put, you stand a good chance of developing a harmful habit if you drink regularly.</p></li><li><p><em>Endogenous preferences</em>. So far I've treated utility functions as given, yet our social dynamics act as microfoundations for them. The externalities driven by the right-tail of alcohol consumption are arguably offset via the cross-subsidisation of hospitality, entertainment, and the arts. Economists refer to such norms and institutions as VCG mechanisms. Yet this is analogous to a value of &#952;=1 (unemployment=vacancies) in a DMP search model, yet v+u rises (Beveridge Curve shifting outwards). VCG mechanisms are endogenous to tastes, and changes in taste can raise welfare within a VCG. One could make the same arguments I've made against abstinence being IC (socially and individually) for smoking too, yet smoking rates have massively declined throughout the last half-century, due to tastes alone.</p></li><li><p><em>Drinking actively increases discount rates</em>, consistent with the disinhibition. This impairs the effectiveness of pricing the externalities, although a social planner could just raise the price higher. Yet this reintroduces distributional and fairness concerns. Should we really lock up drunks for longer or stigmatise them more when those that can take alcohol or leave it can abandon the habit?</p></li><li><p><em>There does not exist a separating equilibrium</em>. Suppose we have two types, &#8220;moderates&#8221; and &#8220;alcoholics&#8221;. Our agent is oblivious to their type ex-ante, and only learns ex-post. Ideally the &#8220;moderate&#8221; equilibrium will drink and the &#8220;alcoholics&#8221; abstain. Yet it's impossible for those entering the drinking culture to make an informed choice regarding their type. This is my main criticism of the Becker and Murphy model, and I would like to augment it with incomplete information and heterogeneity regarding the parameter encapsulating the exogenous drug effects.</p></li></ol><p>What alcohol does have in its favour is the socialisation rituals. I think of our drinking culture as a focal point, especially in Britain where you can make friends simply by being a regular at your local pub. As most people enjoy drinking, our assumption that our friend or date will accept a meeting based on drink is well-calibrated. Substitutes tend to be riskier, especially in the initial stages of investing in social networks (which matter too for human capital). Again, another market-driven solution to textbook market failure. Whilst social media allows for more efficient matches via reducing the search costs to finding like-minded individuals, it can also act as an outside option to in-person socialisation. This is why, when you consider the general equilibrium, I do not blame social media for the decline in in-person socialisation noted by Derek Thompson. I wonder instead the extent to which declining drinking plays a role, although endogeneity is present (people drinking less because they're socialising less). </p><p>In any case, I'm weighting the instrumental utility of alcohol far too highly here, when for most drinking in a quaint bar or pub is immensely pleasurable in itself. We focus far too much on the measurable externalities, and less on the consumer surplus. The very fact that establishments (especially in London!) can set such high equilibrium markups in monopolistic competition is testament to the implicit utility gains of alcohol consumption. Our models and estimates of the social costs vs benefits of alcohol consumption must also incorporate the cross-subsidies to all of in-person social and public life, which is harder hence neglected in the literature.</p><p>Overall, my priors are hence that <em>the social costs do not outweigh the private and social benefits</em>. Our optimal drinking levels can of course be simply derived via our revealed preferences in a rational addiction model. Therefore our concern with drinking is reduced solely to the externalities [5]. On this front, it makes to consider alternative social norms to reduce, if not eliminate, the centrality of drinking to our lives. Here are some preliminary suggestions:</p><ol><li><p><a href="https://x.com/i/status/2029235795047919618">Sentia Gold</a> - a fantastic substitute. In general <a href="https://www.google.com/url?sa=t&amp;source=web&amp;rct=j&amp;opi=89978449&amp;url=https://commons.wikimedia.org/wiki/File:HarmCausedByDrugsTable.svg&amp;ved=2ahUKEwijpa2npvWTAxXWaEEAHft6H3cQFnoECCQQAQ&amp;usg=AOvVaw3gn_dZ_dijOOhdcBuFtQ51">most other substances appear to yield lower tail-risks and externalities</a>, yet may be less amenable to socialisation. Cannabis on net reduces extroversion. Cocaine is often incompatible with dining, and arguably complements alcohol for some users.</p></li><li><p>The sober curious ecosystem. Unfortunately their sober meetups are not nearly as frequent as drinking events, and sober bars not nearly as accessible as pubs or bars. I went to one such event, and I left after half an hour. When the drink itself is the focal point, matches tend not to last. This sharply raises my belief in the hypothesis that the social anxiety search cost is a salient tax. Drink reduces this, agents interact and learn about the other's preferences, which elimimates the asymmetric information and allows more efficient matching.</p></li><li><p>Exploit peer effects. Set an example of the drinking habits you want to see. This is what I try to do.</p></li><li><p>Raise the social penalties for drink-fuelled externalities. Rational addiction implies more, not less, stigmatisation of addicts on the margin whilst penalising most vices a lot less. In general I see this as most conducive to human happiness and flourishing.</p></li><li><p>Give complete information. <a href="https://x.com/i/status/2044557290628436213">Treat people as adults</a>. Do not stigmatise or judge, avoid the sanctimonious appeals to virtue, and drop the paternalism. Have we not learnt from the pandemic? Medical professionals are manipulating their patients with anything else. What I like about Tyler is thag he frames his advocacy of abstinence primarily as mentoring. Appeals to self-interest, as we are indeed selfish creatures, will likely go far.</p></li><li><p>Role models. Teetotalers have an image problem. Where are the fun teetotalers?</p></li><li><p>Outside options. Hencs Tyler&#8217;s emphasis on dining out: a somewhat Straussian rebellion on our drinking culture?</p></li><li><p>Raising fertility. An underrated cost of declining fertility is that virtue is less incentive-compatible. You socialise and party more. You take more risks [6]. With kids, you're forced into contemplating the future.</p></li><li><p>The education rat race. Although from a signalling standpoint this could be suboptimal, and it may negatively impact fertility (again endogeneity: does lower fertility mean parents invest more in education rather than such raising the costs of childbirth?), the returns to low discounting lifestyles relative to high discounting increase. In the time constraint, students allocate more hours to studying and less to partying.</p></li><li><p>Today&#8217;s reduced comsumption in itself. Rational addiction implies some degree of path dependency in alcohol consumption. Less individuals form habits with increasing returns. Less individuals are exposed to alcohol which reduces investment into consumption capital. More individuals having zero initial consumption makes addiction much less likely in the model.</p></li></ol><p>One can conceptualise our questioning of the tradition of boozing, and burgeoning interest in alternatives, as reflective of a culture where low discounting is increasingly high-status. Higher life expectancies raise the returns to lower discounting. In large part, I think this explains the renewed interest in self-help philosophies revolving around this. Our attitudes to alcohol are already undergoing a paradigm shift, as perhaps exemplified by my post. A few years ago, even contemplating the very possibility of abstinence would be unthinkable on my part. Yet we won't sober up via deceiving drinkers on public health grounds. Bryan Johnson, and all those misrepresenting the health consequences of a single drink, are a liability to their cause.</p><p>UPDATE (23/05/2026): Since writing this post, my opinion has actually turned sharply against alcohol. As a corollary of the logic in <a href="https://open.substack.com/pub/microfounded/p/smartphones-and-fertility-a-simple?utm_source=share&amp;utm_medium=android&amp;r=56swa">my latest post</a>, drinking increases the match rate (for both platonic and romantic relationships) via reduced anxiety (as a transaction cost) yet probably reduces matching efficiency (from the logic of this post). Both of these dynamics raise the number of matches (the latter as people are less picky), however the reduced match surplus means the net welare effect of alcohol as a socialisation focal point is ambiguous. The costs however are stark and mostly indisputable. </p><p>Therefore my opinion of drinking has shifted towards it being a bad habit that should be minimised, although I still disagree with paternalistic efforts (and the gaslighting!) to intervene in the lives of others. Since this post, I now average around 10 units per week. Admittedly I don't quite have the discipline necessary to be teetotal, yet I suppose on intellectual grounds I concede to them.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><div><hr></div><ol><li><p>Not all obviously yet certainly those claiming the highly uncertain and imprecise evidence is settled here.</p></li><li><p>It was actually when detoxing when I came across <a href="https://www.google.com/url?sa=t&amp;source=web&amp;rct=j&amp;opi=89978449&amp;url=https://www.economist.com/1843/2025/02/28/tyler-cowen-the-man-who-wants-to-know-everything&amp;ved=2ahUKEwjd5byTiPWTAxUAW0EAHSu5AlMQFnoECA8QAQ&amp;usg=AOvVaw3fpeXqaKiLoQSdkkjkXO4M">this profile</a> of Tyler. Although I've participated in online economics discourse in some form since 2015, I never became a regular MR reader until then. I did recall when my Mum sent me this article that his Wikipedia mentioned he's teetotal. I decided I wanted to be like him, and this was what ultimately motivated me to address my addiction - even if I'm not abstinent (I've done a few trials; my longest period lasting a year), I've certainly gotten my act together! I discuss the role of role models later in the article, yet it's fair to say that Tyler, by showing it is possible to live a fulfilling life sober, deserves a lot of credit for my progress today. I'll always be grateful.</p></li><li><p>This is also an argument against state provision of public goods. Markets have designed norms and mechanisms that incentivise their production.</p></li><li><p>Standard rational choice theory makes no distinction at a given point in the time, yet the latter is clearly at high risk of (re)lapse, so one can introduce a dynamic game of commitment here.</p></li><li><p>To the extent that drinking harms human capital, I prefer <a href="https://open.substack.com/pub/microfounded/p/a-primer-on-economic-growth?utm_source=share&amp;utm_medium=android&amp;r=56swa">endogenous growth models</a> that incorporate diminishing marginal returns to all inputs, otherwise tradeoffs are simply destroyed by Parfit's regugnant conclusion.</p></li><li><p>Although the fact that more patience is correlated with increased risk-aversion is another complication.</p></li></ol><p></p>]]></content:encoded></item><item><title><![CDATA[My postmodern defence of truth]]></title><description><![CDATA[Postmodernists are correct that truth depends on meaning yet meaning does not arise arbitrarily]]></description><link>https://www.ciaranmarshall.co.uk/p/my-postmodern-defence-of-truth</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/my-postmodern-defence-of-truth</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Fri, 10 Apr 2026 14:41:06 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p><a href="https://www.google.com/url?sa=t&amp;source=web&amp;rct=j&amp;opi=89978449&amp;url=https://www.theologie.uzh.ch/dam/jcr:ffffffff-fbd6-1538-0000-000070cf64bc/Quine51.pdf&amp;ved=2ahUKEwjgq_H3s-OTAxVfdUEAHdE6Hk0QFnoECDwQAQ&amp;usg=AOvVaw1evwIYN0r2uDwIYT9pGTXV">Quine famously</a> attacked the very concept of an analytic vs synthetic distinction. Analytic statements are tautologies - true by definition. For instance, &#8220;all bachelors are married&#8221;, &#8220;all triangles have three sides&#8221;, and &#8220;2+2=4&#8221; fall within this category. Meanwhile the truth values of synthetic statements depend on whether such values correspond to the actual state of the world. A prime example would be &#8220;all bachelors are unhappy&#8221;. </p><p>If a statement is true by definition, then it poses the question of what counts as a formal definition, and what makes such correct. This is not so clear cut. The convention is to use the standard rules of deduction given by propositional and first-order logic, whilst performing that arithmetic with the Boolean values to test whether the final statement is tautological. Remember your introductory logic class at college/university? However, the law of the excluded middle and double negation remain contested rules, and alternative logic systems such as intuitionist or G&#246;del logic have arisen as answers to such debates. Therefore the validity of a definition rests in part on our subjective assumptions on which set of deductions are valid.</p><p>Quine's solution is that knowledge and truth operate on an underlying web of connected beliefs over truth values and definitions. If our beliefs are revised, then the analytic statement no longer remains analytic. For instance, suppose that we suddenly change the law and redefine the very concept of a bachelor. Or we use an entirely different group (e.g. modular arithmetic) for our daily calculations. Then &#8220;all bachelors are unmarried&#8221; or &#8220;2+2=4&#8221; no longer become analytic. The former depends on our definitoon of bachelor. The latter becomes (2+2)mod1 = 4mod1 = 0, if we want our formal system to always return an empty value for any inputs, and use mod 1 arithmetic to achieve this. So in principle there are no a priori formal restrictions on what counts as truth. Truth is endogenous to our use of language. </p><p>A more grounded example is that if an object is uniformly red, this is incompatible with it being uniformly black. However black-and-white photography uproots this entire statement. Perception of colour depends on our mental states, which introduces some degree of subjectivity. The sorts of questions raised via discussions of qualia and our consciousness (for instance, is my red your black?) also undermine the notion that this is an analytic statement.</p><p>All of this sounds rather postmodernist. Yet neither is Quine nor I rejecting the very existence of objective truth. It does not follow that, because we lack a fixed and uncontested formal system and set of definitions to define truth ex-ante, objective truth per se does not exist. Our belief systems do not just arbitrarily arise out of thin air, yet are connected deeply to the reality under which the world operates and we live in. This must be the case for our beliefs and languages to yield any sort of utility. We define a concept of a bachelor as our legal and social institutions rely on such a distinction being made. We use base 10 as opposed to modular arithmetic, as we obviously need to count physical objects as they exist around us. Perception introduces a wedge between the mind and objective reality, yet survival relies on either a highly accurate approximation of reality or the ability to accurately perceive most of reality. If my green is your blue, then as long as us two independent observers agree that it is the same colour, then this is the best we can expect when definiting what counts as objective reality? If subjective perception does not generate meaningful variation in observations, then we have just introduced meaningless circularity that for practical purposes do not add to any understanding of our world, so can be erased.</p><p>In general, Tarski sought to overcome this very epistemic relativism. Truth is to be defined via correspondance with a formal system and a meta-system that holds the Boolean values consistent with empirical reality. The beauty in this correspondence is that the very concept of an analytic definition is preserved. We also eliminate any concerns over our use of the excluded middle and so on. If our tautologies and our truth values given by classic logic correspond with our meta-language as given by our beliefs and those truth values, then the distinction very much holds. In this sense, I subscribe to Hilary Putnam's solution to the dilemma.</p><p>Likewise, as Donald Davidson advocates, if truth is conditional on our semantic meanings, then we only need to know such semantic meanings to determine whether a statement is analytic. For instance, I only need know what the term &#8220;bachelor&#8221; means, in tandem with some fluency in English, to know that &#8220;all bachelors are unmarried&#8221;. In a sense, a semantic interpretation of meaning is sufficient for our meta-language.</p><p>What determines semantic meaning? The utility of our words as they correspond to the reality in which we operate in. Postmodernists are correct that meaning is ascribed by ourselves and our societal institutions, as opposed to just arising, yet such meaning yields a vital connection to reality. Even if truth is dependent on meaning, this should not be stretched to imply that objective truth does not exist.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><p></p>]]></content:encoded></item><item><title><![CDATA[April 2026 links]]></title><description><![CDATA[This is actually a good endorsement of economics and political science. Also notable that to the extent the results do fail robustness or replication exercises, the standard errors as opposed to effect signs or magnitudes tend to be impacted.]]></description><link>https://www.ciaranmarshall.co.uk/p/april-2026-links</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/april-2026-links</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Thu, 09 Apr 2026 18:41:04 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<ol><li><p>This is actually <a href="https://x.com/i/status/2039372719947657465">a good endorsement of economics and political science</a>. Also notable that to the extent the results do fail robustness or replication exercises, the standard errors as opposed to effect signs or magnitudes tend to be impacted.</p></li><li><p><a href="https://arxiv.org/abs/2603.28627">Quantum computing is on the path to commercial scalability</a>.</p></li><li><p><a href="https://x.com/i/status/2039047020518707318">Why cannabis hurts brain volume less than we think</a>. As tobacco is a mild stimulant, many consider it a nootropic, which could explain the muted toll on the brain to a lesser extent the cumulative physical health costs might otherwise imply.</p></li><li><p>Why economists <a href="https://x.com/i/status/2039058130554724644">agree with AI researchers</a> that this could be the most transformative technology since at least the industrial revolution.</p></li><li><p>An argument in favour of endogenous growth theories <a href="https://x.com/i/status/2038403133840433385">that focus on human capital</a> rather than spillover effects?</p></li><li><p>&#8220;<a href="https://x.com/i/status/2037832066138624314">Did Paul Mccartney peak after The Beatles</a>?&#8221;</p></li><li><p><a href="https://x.com/i/status/1898893364256297178">Reporting heterogeneity must be assumed a priori for all cross-country comparisons</a>.</p></li><li><p><a href="https://x.com/i/status/2037261635551887660">Publication bias in the discrimination literature</a>. Not surprising&#8230;</p></li><li><p>&#8220;<a href="https://x.com/i/status/2037270166115872776">Direct evidence for negative fertility implications of the educational rat race</a>&#8221;.</p></li><li><p>On <a href="https://x.com/i/status/2036540715807695278">how to carry antiprotons</a>.</p></li><li><p>A lesson in how bottlenecks in the coordination of tasks within an occupation <a href="https://x.com/i/status/2036245912628912132">can generate substantial complementarities</a> for AI and labour as inputs.</p></li><li><p><a href="https://x.com/i/status/2033955718072512517">Even research questions can now be automated</a>. At what point do we expect autonomous AI agents to establish rival academic institutions and networks.</p></li><li><p><a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=6440018">Deregulation boosts "investment, productivity, stock prices, profits, and GDP". Industry-specific shocks "boost industry-level stock returns", so deregulation may impact "incumbent profitability and operational efficiency more than competitive entry."</a></p></li><li><p><a href="https://www.nber.org/papers/w34986">New work</a> is disproportionately enacted by the young and educated at a premium. The fact that employment and premiums respond to demand shocks means this is not coincidence. "By generating new domains of human expertise", they increase employment.</p></li><li><p>A neat means to isolate the magnitude of diagnostic drift - via <a href="https://x.com/i/status/2035798295558095188">a meaurable neurophysiological reciprocal</a>.</p></li><li><p>The <a href="https://x.com/i/status/2035381679708062027">case for the decentralisation of knowledge production.</a></p></li><li><p><a href="https://x.com/i/status/2034626686201852145">Most rich countries produce miniscule levels of plastic pollution.</a></p></li><li><p><a href="https://x.com/i/status/2034706629908664352">Dynare 7 for HANK!</a></p></li><li><p><a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=6191618">"Traders with above-random accuracy earn negative returns because they arrive late and pay unfavorable prices; traders with near-random accuracy profit through superior execution."</a></p></li><li><p>Plausible that Brexit ends up producing sinilar growth dynamics to some endogenous growth theories such as Lucas 1988. An initial shock harms output, yet raises growth in the long-run. <a href="https://x.com/i/status/2034311986574410142">Increasingly Brexiteers have been proven right on regulation</a>, which matters in these debates.</p></li><li><p>How <a href="https://x.com/i/status/2034245424731594865">deep learning</a> could resolve the computational constraints to DSGE estimation?</p></li><li><p>Debunk economics misinformation <a href="https://x.com/i/status/2033944747409080819">here!</a></p></li><li><p>&#8220;<a href="https://x.com/i/status/2033597122952438094">Sonnet 4.6 prefers autocorrelation and level OLS. Opus 4.6 likes to choose variance ratios and log OLS. Your research results might depend entirely on which LLM you use</a>&#8221;. So do not expect AI automation to resolve all the issues of emprical science just yet. Uncertainty in our estimates is always positive. However AI may still be <a href="https://x.com/i/status/2033701367165161477">less prone to false positives</a> than peer reviewers, suggesting their use in social science research will not disappear.</p></li><li><p>Even the <a href="https://x.com/i/status/2034071186267603383">Amish use washing machines</a>.</p></li><li><p><a href="https://x.com/i/status/2033971342614401531">Is vegetarianism the latest longevity fad?</a></p></li></ol><p></p>]]></content:encoded></item><item><title><![CDATA[A theory of moral complementarity]]></title><description><![CDATA[What Hinduism can teach us about modern debates in ethics]]></description><link>https://www.ciaranmarshall.co.uk/p/a-theory-of-moral-complementarity</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/a-theory-of-moral-complementarity</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Thu, 09 Apr 2026 14:03:43 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p><strong>What Hinduism can teach us about modern debates in ethics</strong></p><p>I'm currently reading the Mahabharata and the Ramayana. What strikes me about the former is the extent to which even the protagonists engage in Machiavellian and seemingly amoral conduct. I view this as a tale in the pitfalls of strict deontological rules. In this sense, dharma pioneered (without explicitly defining or formalising the concept) utilitarian and consequentialist ethics. Unlike most other faiths, the inherent tradeoffs plaguing any moral decision are emphasised ex-ante. An alternative interpretation is that the main lesson is the inevitability of evil and suffering in life despite the best intentions of most, which grounds the tale firmly as a class in human nature.</p><p>If the Mahabharata, via myth and literary masterpiece, outlined our core moral theory, the Ramayana introduced the ingredient of virtue - the necessity of acting based on our morals even in the face of adversity. Hindus recognise the main flaw in utilitarianism: a vague consequentialist framework can easily be manipulated for self-serving, as opposed to ethical, purposes. It's very easy to argue that one's selfish decisions are motivated for the good of the overall community, if preferences are unknown to the individual.</p><p>Yet this introduces the question: how do we know if we're truly acting virtuously with courageous endeavour, rather than falsely believing such or rationalising ulterior malicious motives? If dharma is context-dependent and consequences unknown, haven't we just reintroduced the very moral relativism we sought to avoid? Surely we return to the very rigid deontological constraints that the Mahabharata subtly warned us about? </p><p>This is where the roles of myth, storytelling, and faith enter our human universals. Whilst lacking in epistemological or logical rigour, <a href="https://open.substack.com/pub/microfounded/p/occultism-as-a-secular-alternative?utm_source=share&amp;utm_medium=android&amp;r=56swa">these heuristics provide a parsimonous framework on how to act</a>: in our daily lives, for life's inevitable tragedies, and our most difficult decisions where we may otherwise be paralysed by our conscience. The lack of logical consistency, if we accept from G&#246;del the inherent tradeoff between consistency and parsimony, tends to avoid the costs of following deontological instructions to the expense of our welfare. Yet a broad set of heuristics, that can be broken in special cases (highlighted in the canon and the evolution of its interpretations through time), focuses on optimising utility on average as opposed to each and every case. Often the focus on imitating role models - the main prophets of the Abrahamic faiths, Aurelius for the stoics, and the &#252;bermensch of Nietzscheans - adds emotional relevance through empathising with our plights and inspiring us to be our best selves. By placing ourselves within their shoes and asking &#8220;what would they do?&#8221;, with the famous myths corresponding to a particular dilemma salient in our minds, the ethical decision becomes apparent. For dharma, we introduce Rama for this very purpose.</p><p>An underrated reason for the existence of role models that now occured to me, just as I write this sentence right now, is that they provide the motivation to act more altruistically and self-sacrificing on the margin. Effective altruists and the underlying philosophical inspiration from Singer's drowning child advocates for effectively ceding our utility functions to an empirical calculation of our spending and lifestyles to maximise our philanthropic impact regardless of our own desires. Yet this is obviously blank-slateist. Nonetheless, more self-sacrifice on the margin clearly can be Pareto efficient: this thesis is implicit from prisoner's dilemma games and the free-rider. Economics emphasises the role of institutions and mechanism design to induce less free-riding. Our moral guidance from the legendary classics and our heroes is another means, grounded in our primate emotions, that for the entirety of civilisation we achieve this.</p><p>One could also consider the Mahabharata as a positive theory of morality, and the Ramayana as a normative case for living a life of virtue. Utilitarianism emphases the former, and our intuitions grounded in human universals and our religious beliefs the latter. The former outlines the case, the latter grants it legitimacy via soliciting emotional acceptance. Ultimately, both actually can be considered <em>as complementary, as opposed to competing ethical perspectives</em>. If we accept this line of reasoning, then does modern philosophical discourse exaggerate the disagreements?</p><p><strong>Does the objectivity of morality imply virtue ethics?</strong></p><p>If this complementarity holds, then this lends credence to the notion of <em>morality as objective</em>. From a metaphysical idealist perspective, objective reality (the set of objects that can, in principle, be sensed by more than one independent observers) can consist of abstract as well as physical objects. Hence moral disagreements are concerned not with whether there exists a moral course of action, but rather what that action is. Rather than our debates revolving around the core ontology, they instead exist given the imperfect information that each moral actor holds, which thereby often prevents certainty in knowing what the moral decision is. </p><p>I think this objectivity and complementarity is demonstrated by the fact that almost all faiths, at all times and places they arose independently even when lacking contact with outside cultures, emphasise some concept of self-sacrifice or self-restraint for the moral good. Almost all have reproduced (Aristotelian) virtue ethics from first principles. What religion or moral ideal promotes the idea of being selfish and indulging oneself, even to the expense of your duties, self-maintenance, and your community? Although objectivists place little weight on the values of altruism, the intertemporal aspect of virtue is rewarded a central role. Restraint, delayed gratification, and the importance of duty, are all vital principles that objectivists live by. Even the Cyrenaics and the Epicureans valued some degree of virtue and altruistic behaviour, paradoxically as a means towards achieving individual hedonistic pleasure. Note that all of this is consistent with adopting a utilitarian and consequentialist approach to evaluating ethical tradeoffs, and that such does not imply relativism. In fact, many of the most famous utilitarian philosophers, such as Peter Singer, argue that utilitarianism implies the opposite, that morality is objective.</p><p>A reasonable conclusion to draw is that <a href="https://open.substack.com/pub/microfounded/p/hedonists-embracing-virtue?utm_source=share&amp;utm_medium=android&amp;r=56swa">virtue ethics</a>, <a href="https://open.substack.com/pub/microfounded/p/in-praise-of-hedonism?utm_source=share&amp;utm_medium=android&amp;r=56swa">the set of lifestyle philosophies emphasising</a> <a href="https://open.substack.com/pub/microfounded/p/in-defence-of-a-positive-discount?utm_source=share&amp;utm_medium=android&amp;r=56swa">low discounting</a> and altruism, can be considered a human universal. I have at times throughout the past advocated vociferously against attempts to reduce (via social stigma) the relative status of hedonism, and still consider this paternalistic sentiment to render most individuals worse off overall. The particular avocations of vice we stigmatise, and the magnitude of this social penalty, is not exactly correlated with the social harms such indulgence yields anyhow. At the margin, we could clearly do with less judging, and more of &#8220;live and let live&#8221; approach to the habits of others. However, concerning the total effect, the optimal level of belief in virtue ethics is probably nonzero. If such a philosophy has been replicated independently across distinct times and places throughout human history, and remained prevalent since, then a Burkean view on institutions considers such as facilitating our social and cultural wellbeing, and therefore is culturally and biologically adaptive. </p><p>However, an alternative interpretation is that these philosophies instead aim to spin the ubiquity of suffering in a positive light. Tragedy is instead framed as heroic glory, and a courageous pursuit of a higher virtue. By raising the relative status of suffering, not only are individuals more likely to sacrifice themselves for the good of their polity (necessary when war was so commonplace to in effect be our default state), but the cardinal costs such suffering imposes are alleviated. To an extent, the Stoics and Buddhists are right that some proportion of our pain is influenced by our emotional perception of it. Whilst such appeals to virtue may have dulled the pain of the Malthusian poverty characterising most of human existence, in an era of unprecedented abundance, should we not rethink the valorisation of tragedy? </p><p>Even I find the concept of virtue ethics intuitively appealing on aesthetics, yet this line of reasoning amounts to little more than &#8220;the vibes align with my emotional priors&#8221;. If virtue is indeed always in our self-interest, then why do lofty appeals to such prevail over binding contracts? Why do even self-enforced commitments to lifestyle changes tend to fail? When the incentives of committing to an ethical heuristic tend to fail, then should we update our normative views on its merits? The answer is that, as is the central lesson of game theory, that what is biologically and culturally adaptive hence socially optimal is not always consistent with individual optimisation. Therefore we design a set of social norms to coordinate this shift to the greater good. This is how human universals accelerate cultural and natural selection.</p><p>UPDATE (11/05/2026): Recently I was thinking about optimal taxation, and on reflection, there are lessons for the utility of utilitarianism. Generally, in optimal taxation and tariffs papers, a benevolent social planner maximises a social welfare function subject to constraints such as labour supply responses. This set up makes the flaws in utilitarian calculation apparent. </p><p>As Hayek and Burke demonstrated, there does not exist a social planner that holds complete information regarding everyone's cardinal and ordinal preferences (assuming rationality, the two are equivalent). In Walrasian equilibrium, this is not an issue provided that the axioms of Arrow's first theorem are satisfied, yet that clearly is not the case. There also exists suboptimal NE with limited participants. In selecting policy, Arrow's impossibility theorem and Gibbard-Satterthwaite demonstrates that all aggregation rules are inefficient or dictatorial. Moreover, public choice theory disproves the notion of a social planner as benevolent (maximising a SWF as opposed to the interests of those participating in political institutions).</p><p>Therefore, we lack a reliable means to state with certainty what the utilitarian outcome is. Effective altruists not only ignore the calculation problem, but go further than most economists in assigning utils (cardinality), which is why I am not entirely convinced by the movement. However, if we were to adopt a Burkean stance on ethics to its most extreme, we get something along the lines of the Confucianism of the Chinese Empires, which is not only excessively rigid but a major factor in China's relative isolation from the world until the last century or so.</p><p>As such, perhaps the role of stoicism is to tradeoff these costs and benefits of crude pleasure maximising (which as we have seen may not generate efficient outcomes) vs being responsive enough to incentives and facilitating creative destruction. Stoicism departs from Eastern concepts of virtue by emphasising the role of individual agency over social hierarchy and authority. Of course, in our models, the relevant margin of adjustment is the discount rate. Whilst discounting is justified, on the margin our world can clearly benefit from a reduction in this parameter. Besides, low discounting tends to produce happier lives in the long-run anyhow. How else would you explain why unemployment or inactivity causes depression, if labour is considered a disutility in our models?</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><p></p>]]></content:encoded></item><item><title><![CDATA[Alien UFOs spotted?]]></title><description><![CDATA[Yes we should take Villarroel's findings seriously]]></description><link>https://www.ciaranmarshall.co.uk/p/alien-ufos-spotted</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/alien-ufos-spotted</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Sat, 04 Apr 2026 14:09:03 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p><a href="https://x.com/DrBeaVillarroel/status/2039621764368527843">Recently we've seen</a> <a href="https://x.com/i/status/2036379674477998209">independent confirmation of Villarroel's findings</a>, <a href="https://x.com/i/status/2039734048436945238">with the latest out yesterday</a>. For those whom usually dismiss talk of UFOs as conspiratorial quackery (which I assume will be most of my readers), last year Beatriz Villarroel and coauthors parsed through the earliest astronomical images using modern algorithms optimising pattern spotting, and discovered transients in space observed pre-Sputnik, <a href="https://sciety-labs.elifesciences.org/articles/by?article_doi=10.21203/rs.3.rs-6347224/v1">correlated with reported UFO sightings</a>. <a href="https://www.researchgate.net/publication/394040040_Aligned_multiple-transient_events_in_the_First_Palomar_Sky_Survey">Here's the abstract</a>:</p><blockquote><p>&#8220;Old, digitized astronomical images taken before the human spacefaring age offer a rare glimpse of the sky before the era of artificial satellites. In this paper, we present the first optical searches for artificial objects with high specular reflections near the Earth. We follow the method proposed in Villarroel et al. (2022) and use a transient sample drawn from Solano et al. (2022). We use images from the First Palomar Sky Survey to search for multiple (within a plate exposure) transients that, in addition to being point-like, are aligned along a narrow band. We provide a shortlist of the most promising candidate alignments, including one with 3.9 sigma statistical significance. These aligned transients remain difficult to explain with known phenomena, even if rare optical ghosting producing point-like sources cannot be fully excluded at present. We explore remaining possibilities, including fast reflections from highly reflective objects in geosynchronous orbit, or emissions from artificial sources high above Earth's atmosphere. We also find a highly significant (&#8764;22&#963;) deficit of POSS-I transients within Earth's shadow when compared with the theoretical hemispheric shadow coverage at 42,164 km altitude. This deficit is still present though at reduced significance (~7.6 sigma) when a more realistic plate-based coverage is considered. This study should be viewed as an initial exploration into the potential of archival photographic surveys to reveal transient phenomena, and we hope it motivates more systematic searches across historical datasets.&#8221;</p></blockquote><p>In particular, the novelty in these findings is in <a href="https://academic.oup.com/mnras/article/546/2/staf1158/8221885">the methodology used</a> to test for possible UFOs. Rather than simply count all pre-Sputnik transients (vulnerable to measurement errors and interference, or random noise in the atmosphere<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-1" href="#footnote-1" target="_self">1</a>), they exploited the geosynchronous orbit and isolated the effects of Earth's shadow. For any given orbit, we can calculate whether the Earth blocks sunlight at a particular point. If transients arise from <a href="https://open.substack.com/pub/overcomingbias/p/many-big-pre-sputnik-earth-orbit?utm_source=share&amp;utm_medium=android&amp;r=56swa">glints</a>, we should see far more transients in regions exposed to sunlight relative to within the shadow. </p><p>This is indeed the case, using the rate at which we'd expect transients in the same spot in the absence of shadow. As Robin Hanson noted, the discrepancy between this rate and actual observations (around 2/3) is roughly the same for two orbits at different radiuses, so our findings are consistent with the constraints from math. This discrepancy, from our calculations, also gives the expected number of transients that are glints.</p><p>Moreover, Hanson calculates (adjusting for advances in telescopes) that these are likely to be flat objects:</p><blockquote><p>&#8220;At GEO it would take an ideal ~22-35 cm diameter circle (perfectly flat, aligned, and reflective) to create a magnitude 15-16 image in these photos from a 0.04 sec glint. (Or so says ChatGPT5.) For magnitude 17-19, that changes to an ideal 6-14 cm circle. Objects less than perfectly flat, aligned, or reflective, or with shorter duration glints, would have to be larger. Objects close to Earth could have smaller areas due to that, but would also have to be larger due to closer objects orbiting faster.</p><p>Thus while today Earth sees ~1800 glints per hour off of the roughly ~1-2cm equivalent diameter ideal circle sized human satellites and debris, in the decade before Sputnik, the space around Earth generated ~340 glints per hour mostly from brief (&lt;0.04s) glints of sunlight off of at least roughly 6-14cm equivalent ideal circles. While this makes the older glint distribution seem different from today&#8217;s, note that the older telescope couldn&#8217;t see the fainter glints that today&#8217;s telescopes can see. So the two distributions might actually be the same.&#8221;</p></blockquote><p>Therefore we can plausibly rule out random atmospheric or measurement disturbances, at least at the distances involved. Whilst the possibility of these transients being <a href="https://x.com/i/status/2039811462017753188">cosmic ray flashes</a> is very much alive, the correlation with nuclear tests is consistent with alien civilisations subtly<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-2" href="#footnote-2" target="_self">2</a> warning us about the existential risks involved for us and possibly extraterrestrial civilisation. On a more general note, it's useful to discipline our thinking by considering the incentives alien civilisations have to communicate with us in only a discreet manner - interpreted by (possibly) only top militaries. It seems odd that aliens wouldn't want to make themselves known right? Hanson<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-3" href="#footnote-3" target="_self">3</a> arrives at <a href="https://open.substack.com/pub/overcomingbias/p/ufos-what-the-hellhtml?utm_source=share&amp;utm_medium=android&amp;r=56swa">similar conclusions to mine</a>, with an added emphasis on our likelihood of casting them in the out-group should they attempt peaceful communication<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-4" href="#footnote-4" target="_self">4</a>.</p><p>Ergo if you accept these findings (it's worth noting that <a href="https://www.researchgate.net/publication/400237065_Critical_Evaluation_of_Studies_Alleging_Evidence_for_Technosignatures_in_the_POSS1-E_Photographic_Plates">some have failed to replicate Villarroel's results</a>, so admittedly the findings are noisy<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-5" href="#footnote-5" target="_self">5</a>), the very high likelihood of these transients being glints pre-Sputnik should update your priors. What are the odds that these glint observations are timed coincidentially with reports or nuclear tests<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-6" href="#footnote-6" target="_self">6</a>? </p><p>In any case, a reasonable base rate for our priors regarding the number of alien civilisations communication is possible with, is of course constrained by the Drake equation. Given the billions of stars and planets in the Milky Way, even tiny increases in the probability of extraterrestrial life (which nascent discoveries of biosignatures have confirmed<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-7" href="#footnote-7" target="_self">7</a>) massively increases this number. Assuming heterogeneity in technological development, surely at least some yield the ability to communicate across multiple light-years? So why should our priors be that the number of suspected reportings are in fact alien UFOs are zero? In my view, the burden of proof rests on those that discount this possibility.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-1" href="#footnote-anchor-1" class="footnote-number" contenteditable="false" target="_self">1</a><div class="footnote-content"><p>The Palomar telescope used plates sensitive to both red and blue light, so electromagnetic dynamics could distort the observed findings).</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-2" href="#footnote-anchor-2" class="footnote-number" contenteditable="false" target="_self">2</a><div class="footnote-content"><p>Subtle as to not generate future retaliation nor to be interpreted as signs of aggression. This hypothesis would be consistent with the classic military conspiracy where knowledge of aliens is silenced with stark penalties for whistleblowing, in order to not &#8220;alarm&#8221; the world or countries outside the military frontier.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-3" href="#footnote-anchor-3" class="footnote-number" contenteditable="false" target="_self">3</a><div class="footnote-content"><p>I dislike appeal to authority arguments, but with the &#8220;Great Filter&#8221; hypothesis, Hanson has made important advancements in astronomy as well as in economics. In this respect he's somewhat of a polymath, and an expert in this topic. Hence the existence of alien UFOs visible from Earth yields support from credible academic and scientific figures with the relevant credentials, not just the usual assortment of cranks and conspiracy theorists.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-4" href="#footnote-anchor-4" class="footnote-number" contenteditable="false" target="_self">4</a><div class="footnote-content"><p>Read the history of European discovery of the new world, and they weren't welcomed by indigenous civilisations either, even with trading opportunities and without forced conquest or slavery. Arguably entrenched popular opposition to globalisation (freer trade and migration) is itself a relic of our aversion to other civilisations.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-5" href="#footnote-anchor-5" class="footnote-number" contenteditable="false" target="_self">5</a><div class="footnote-content"><p>Notwithstanding the fact that &#963; rather than p-values is our test for significance here, which is a much higher bar.</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-6" href="#footnote-anchor-6" class="footnote-number" contenteditable="false" target="_self">6</a><div class="footnote-content"><p>One hypothesis noted in the last paper I cited suggests that, given that telescopes don't observe on all days, the correlation arises from the fact that the observation schedule was coincidentially aligned with the dates of nuclear tests. Yet there's independent replication of this correlation too, suggesting some level of invariance once normalising for observation days?</p></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-7" href="#footnote-anchor-7" class="footnote-number" contenteditable="false" target="_self">7</a><div class="footnote-content"><p>I forgot to hyperlink to my Substacks showing these findings. I can't seem to hyperlink on the edits, which requires going into the Chrome browser rather than the app. You can find the relevant links here: https://open.substack.com/pub/microfounded/p/what-i-have-been-reading-mid-september?utm_source=share&amp;utm_medium=android&amp;r=56swa</p><p>https://open.substack.com/pub/microfounded/p/what-i-have-been-reading-october?utm_source=share&amp;utm_medium=android&amp;r=56swa</p><p>https://open.substack.com/pub/microfounded/p/what-i-have-been-reading-mid-october?utm_source=share&amp;utm_medium=android&amp;r=56swa</p><p>https://open.substack.com/pub/microfounded/p/mid-december-2025-links?utm_source=share&amp;utm_medium=android&amp;r=56swa</p></div></div>]]></content:encoded></item><item><title><![CDATA[Occultism as a secular alternative to faith?]]></title><description><![CDATA[Esotericism stems from the impossibility of knowing everything about the universe and how it operates.]]></description><link>https://www.ciaranmarshall.co.uk/p/occultism-as-a-secular-alternative</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/occultism-as-a-secular-alternative</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Sun, 29 Mar 2026 15:07:55 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p>Esotericism stems from the impossibility of knowing everything about the universe and how it operates. Straussianism is an inherent feature of the physical world. Reality is not only what can be empirically sensed. However, one can supposedly uncover these &#8220;hidden&#8221; meanings and phenomena via a subset of rituals that we refer to as occultism. These include practices such as magic, astrology, alchemy, contacting spirits, witchcraft, and so on.</p><p>Within occultism, there are a plethora of broad traditions. Hermeticism emphasises our divine transformation via gnosis (esoteric knowledge) as a path to revealing the hidden mechanisms of the cosmos. Kabbalah attempts to formalise esoteric theory and the interpretations of symbolic representations. The relationship with the neopagan faiths runs deep. Of course, occultism is defined just as much via practice and implementation as theory. Ceremonial magic explicitly seeks contact and alignment with supernatural forces via an elaborate set of rituals designed to achieve spiritual transformation. Thelema argues that we each have a hidden &#8220;true&#8221; purpose for our existence, and this defines the meaning of life - Thelemites tailor magic towards uncovering this individual meaning. Chaos magic is less dogmatic, and will borrow more heavily from established science.</p><p>Like rationalists (of the D&#233;scartes rather than the LessWrong tradition!), the idea that reality is only what we can sense is rejected. Where they differ is obviously via the manner in which they seek this knowledge. The former emphasises formal logical deduction and proof from axioms; the latter vague symbols and superstition, unfalsifiable rituals, and the &#8220;supernatural&#8221; as a residual for our ignorance. There are no prizes for guessing which epistemological framework I'm more sympathetic to! Despite this, an advantage of esotericism over rationalism is that it seems more aligned with those seeking a life meaning: guidance, often in the form of personalised ceremonial activities, on how to live. Moreover, modern science essentially relied upon occultist practices in its heyday. Chemistry would not exist without alchemy. Kepler was infamous for practicing astrology. Arguably, a focus on decoding hidden processes broke us out of the Dark Ages into the Enlightenment, by shackling us away from a dependence on God as the default explanation for everything. Modern science, via wildly different methods, also seeks to decipher hidden phenomena, if we consider &#8220;hidden&#8221; as synonymous with &#8220;unknown&#8221; in this context.</p><p>We can test the robustness of astrology as a theory of the universe via <a href="https://en.wikipedia.org/wiki/Astrodatabank?utm_source=chatgpt.com">tracking the accuracy of its predictions</a>. Once we account for sampling error, astrological predictions seem to perform no better than random chance (although an astrologer would argue that randomness is determined by some esoteric mechanism). Hence this entire epistemological framework is not only unfalsifiable, but cannot be justified via a Bayesian standpoint either. So what explains its continued popularity?</p><p>I'd argue that the widespread demand for this pseudoscience is grounded in the desire to seek a secular replacement for the meanings and practices that religious institutions provide. Science has not displaced religion, as science cannot answer how we should live life. Religion provides a ready-made template for practical ethics that can be applied throughout our daily lives, with celestial enforcement and a philosophy of meaning to incentivise the prosocial. A core cognitive bias is that we seek and accept nonrandom explanations for random phenomena or coincidences, which is why we're often susceptible to astrological predictions proving correct or supposed miracles and answered prayers. To a large extent, wishful thinking - the desire to place a positive spin on life's ubiquitous tragedies, suffering, and evils - also prevails<a class="footnote-anchor" data-component-name="FootnoteAnchorToDOM" id="footnote-anchor-1" href="#footnote-1" target="_self">1</a>. Then of course art and beauty is commonly motivated via the pursuit of a higher power - our cultural lives would be drastically inferior with the absence of religion.</p><p>Religion is increasingly being falsified, with claim after claim regarding metaphysics in the Bible being falsified, and hasty Straussian reinterpretations ex-post to maintain legitimacy via consistency with science. Nonetheless, it clearly serves a purpose in the advancement of our prosperity and a fulfilling life, so these superstitious institutions will never vanish. Faith, myth, and ritual, with the derived practices, are classic human universals. </p><p>Therefore, occultism is rising as a viable substitute. Indeed, practitioners of the occult seem to have learnt from the mistakes of established religions. Don't offer certain testable hypotheses that could be refuted in the future, but instead offer vague statements that can easily be interpreted to fit the facts. This is essentially the entire premise of astrology, which is why even devout atheists have an easier time accepting this philosophy. Moreover, occult practices also place an important emphasis on individual agency, so is compatible with the increasing demand for virtue ethics as exemplified via the nascent resurgence in stoicism. Plus unless you're in a literal cult, the demands for commitment and adherence are also a lot less rigid than established religions. You can essentially drop in and out, and take whatever belief you want, as you please. You cannot do this with religion.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><div class="footnote" data-component-name="FootnoteToDOM"><a id="footnote-1" href="#footnote-anchor-1" class="footnote-number" contenteditable="false" target="_self">1</a><div class="footnote-content"><p>This is why I think the problem of evil misconceptualises the underlying theme regarding God's existence. Belief in God essentially relies on evil. Faith exists precisely to direct individuals away from evil. God provides an obvious psychological comfort blanket.</p><p></p></div></div>]]></content:encoded></item><item><title><![CDATA[Mid-March 2026 links]]></title><description><![CDATA[Dollar dominance is cyclical?]]></description><link>https://www.ciaranmarshall.co.uk/p/mid-march-2026-links</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/mid-march-2026-links</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Wed, 25 Mar 2026 19:46:04 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<ol><li><p><a href="https://x.com/i/status/2033166605429965009">Dollar dominance is cyclical?</a></p></li><li><p><a href="https://x.com/i/status/2033065724684677463">An AI agent to debate with</a>.</p></li><li><p><a href="https://x.com/i/status/2032922855357177900">The death of age gaps in relationships</a>.</p></li><li><p>&#8220;<a href="https://open.substack.com/pub/johnhcochrane/p/efg-review?utm_source=share&amp;utm_medium=android&amp;r=56swa">Hayek taught us long ago that it&#8217;s nearly impossible to determine what a price should be</a>&#8221;. Relevant for the literature on markups and monopsonies.</p></li><li><p><a href="https://x.com/i/status/2032750499129180393">Empirical support for FTPL?</a></p></li><li><p><a href="https://x.com/i/status/2033230847663342056">BMI is a good proxy for obesity</a>, despite what you want to think.</p></li><li><p><a href="https://x.com/i/status/2032152281680838907">A vaccine for dengue!</a></p></li><li><p>In other words, <a href="https://x.com/i/status/2031760829872300515">internet anonymity will soon be a crime in Britain</a>. Although AI makes this largely redundant anyhow, this is signalling more than that&#8230;</p></li><li><p>Institutional investors in housing are in fact <a href="https://x.com/i/status/2032141947708506579">a boon for social mobility</a>.</p></li><li><p>AI reduces the costs of debunking misinformation too, <a href="https://x.com/i/status/2032089607643209998">economics edition.</a> Then of course you also have Refine for researchers.</p></li><li><p>&#8220;<a href="https://x.com/i/status/2031533242877112719">Nutrition science is the area of science that's suffered the most in the replication crisis</a>&#8221;. Admittedly I never realised the replication crisis applied just as strongly to a physical science too. Obviously this imposes doubts on the validity of my entire longevity series, hence why I retracted it (theoretically I could've replicated each and every paper I cited, yet that would've been highly time-consuming). If I'm wrong, I'll never double-down: I admit graciously whilst changing my mind, and everything posted on this Substack is perpetually up for review as my epistemic habits mature or the literatures evolve. Another common criticism of that series was excessive citation of modest effect sizes (often via their reciprocals - implausible dosages required to generate the equivalent effect sizes in humans), so I'll be mindful of this going forward. In general, the reliance on using <a href="https://x.com/i/status/1994889039804268666">the model organism equivalent of toddlers</a> in the longevity field plagues the external validity of its claims; notably the calorific restriction results only hold as metabolic defects typical of early childhood clear.</p></li><li><p><a href="https://x.com/i/status/2030820935733825802">Hmmm</a>. I was suspicious that selection bias would undermine whatever findings came out of Aella's survey (name someone not terminally online whom has heard of her?). Can we take from this that sample size and balance on observables seems to be sufficient for representativeness?</p></li><li><p><a href="https://x.com/i/status/2030834046914228638">Well said</a>! If you asked me, &#8220;is there one person on Earth whom you wish to emulate?&#8221;, then Tyler comes close (teetotalism aside, which I wouldn't have even attempted were it not for him). Indeed, the primary goal of this blog is that when he dies and if MR goes along with him, that this Substack becomes a viable and suitable heir.</p></li><li><p><a href="https://x.com/i/status/2028849107180175541">But I thought multiculturalism was destroying the West&#8230;</a></p></li><li><p><a href="https://x.com/i/status/2030060225227805093">The extent to which voters' views are shaped by partisanship and vibes never ceases to amaze me to this day.</a></p></li><li><p><a href="https://www.nber.org/papers/w34547">This</a> is the best evidence I've seen on the causal link between poverty vs crime. RCT. Pre-registered. You don't get much better than this.</p></li><li><p><a href="https://x.com/i/status/2029471122127790511">Take synthetic control papers with a pinch of salt</a>. Note that this doesn't mean the methodology is entirely junk; it's a research direction that yields promise. Often there's no alternative to stimulating likely counterfactuals.</p></li><li><p><a href="https://x.com/i/status/2029795598740734240">Eid vs Bayram</a></p></li><li><p>As Ben Southwood <a href="https://x.com/i/status/2036749685600239862">mentioned earlier</a>, the British government has an unhealthy addiction to <a href="https://x.com/i/status/2029179561624182958">stealth taxes</a>.</p></li><li><p>On the ubiquity of <a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=5245652">insider trading</a>. Also worth mentioning that an underrated benefit of prediction markets is that they harness insider trading for social gain: by incorporating this information explicitly into prices, they allow for more efficient trades. There's no reason not to legalise them in Britain.</p></li></ol><p></p>]]></content:encoded></item><item><title><![CDATA[What Abundance and open borders supporters get wrong]]></title><description><![CDATA[A measured critique from a supporter of these policies]]></description><link>https://www.ciaranmarshall.co.uk/p/what-abundance-and-open-borders-supporters</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/what-abundance-and-open-borders-supporters</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Mon, 16 Mar 2026 17:49:22 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p>Last Saturday, a major empirical result demonstrating agglomeration effects from density <a href="https://x.com/i/status/2032516074739274111">failed to withstand replication</a>. Indeed this mirrors the earlier infamous revisions to Hsieh and Moretti (2019) showing an abnormally large cost of housing regulations to economic growth. A few days ago, Tyler Cowen made a meticulous observation of the general equilibrium effects of land-use policy on social mobility and networks <a href="https://marginalrevolution.com/marginalrevolution/2026/03/some-simple-spatial-analytics-of-cape-town.html">in Cape Town</a>. All of this induced me to ponder about the reliability of the empirical microeconomic evidence for positive spillover channels, and agglomeration, exerting a positive impact on innovation and growth. </p><p>Our priors from <a href="https://open.substack.com/pub/microfounded/p/a-primer-on-economic-growth?utm_source=share&amp;utm_medium=android&amp;r=56swa">endogenous growth theory</a> still appear to be <a href="https://chatgpt.com/share/69b83174-ad34-800a-84a7-e75d4f6ba411">supported by the causal literature</a>. I would of course qualify with a distinction between density and proximity: more apartments in a taller block won't do much to impact innovation (if you've ever lived in one of these and a suburb, everyone knows you're far more likely to interact with neighbours in the latter than former!), yet being sufficiently close for regular face-to-face, and spontaneous interaction, appears to do so.</p><p>However, this raises an obvious tradeoff. Cape Town holds some of the most stunning natural scenery close to a major urban hub that one is likely to find. Natural beauty is nonrival, just as the positive spillovers of innovation are. Can this justify NIMBYism, and offset the welfare losses imposed via maintaining a semi public good?</p><p>To avoid plaigiarising ChatGPT's work, I implore you to read the entire chat, yet in most cases it's clear that NIMBYism exerts a negative cost to welfare. There's even a structural model to interpret the empirical literature and estimates (I would exercise the usual caution that one should with LLM generated work). However, in a few select cases, it's optimal to protect the natural environment in question from development [1]. </p><p>How one calibrates policy, political incentives, and urban planning to incorporate this is a subject for another day: the overrarching thesis that Abundance cannot neglect that there are legitimate [2] cases when local communities might decide to block a development. My first-best solution would be for wealthy philanthropists to protect the undeveloped bucolic habitat via purchasing the land. As we don't have a free-market in land ownership, we must settle for a second-best mechanism design of permitting rules, which inevitably involves some deliberative and collective involvement of third-parties. If YIMBYs are to maximise their popularity, they should find an incentive-compatible solution to streamline when a development can be blocked to protect an overwhelmingly popular public space or not. Yes, small yet vocal activist and bureaucratic interests should not take advantage of the decentralised and litigious nature of planning applications, yet their voice shouldn't be discarded altogether.</p><p>Moreover, the existence of land-use restrictions also changes the calculus on open borders [3]. The most convincing argument in favour of some immigration restrictions stems from Garrett Jones: mean national IQ matters for economic prosperity via institutional quality, immigrants maintain most of their culture and traits [4], so open borders will result in a decline in institutional quality via importing a high number of third-world migrants; exerting a negative effect on governance. British councils adopting what are, in effect, blasphemy laws, are testament to this hypothesis. Rising rates of urban knife crime in Britain - unusual in a context of otherwise declining crime of all types, is primarily a feature of black inner-city gangs, and can be partly explained via a rise in the black population. Previously, I would have critqued this highly compelling critique of open borders with the unduly wise skepticism that any alternative amounts to governments engaging in social engineering regarding demographics and labour markets, which is obviously suboptimal given the track record of central planning in any other circumstance. Most immigrants and their descendents don't commit crime, so just increase policing resources and sentences in line with any shift in immigration trends, if this is your concern. As the Gulf states show, one can maintain the overall quantity and quality of your innovation with an elite right-tail. Additionally though, there is another flaw in Jones&#8217; argument, grounded explicitly in land-use policy.</p><p>Here in Britain, it's common knowledge that minorities in major metropolitan centres perform much better on social mobility, as measured via all the usual means (for instance, going to university conditional on your parents not going, income and employment conditional on parental income, etc), than working-class whites in the North. Presumably, both groups start with a similar genetic endowment regarding IQ. In my view, this is convincing evidence that proximity to hubs of dynamism and progress facilitates mobility. This also substantially mitigates the concerns of immigration restriction advocates, as integration of the second and third generations is a lot more feasible than they think. Despite the noticeable nascent trend towards the hereditarian position on genetic inheritance of traits, environment still indeed plays a large role. Heritability of IQ is likely to be between 50%-60%, in line with most estimates for other traits: slightly below the twin studies estimates yet well above the molecular ones, which aligns neatly with <a href="https://open.substack.com/pub/microfounded/p/what-can-twin-studies-tell-us-about?utm_source=share&amp;utm_medium=android&amp;r=56swa">my perspective</a> <a href="https://open.substack.com/pub/microfounded/p/mid-december-2025-links?utm_source=share&amp;utm_medium=android&amp;r=56swa">on their</a> <a href="https://open.substack.com/pub/microfounded/p/what-i-have-been-reading-december?utm_source=share&amp;utm_medium=android&amp;r=56swa">respective biases</a>. Hence, there is a large scope for both environment and policy (most notably housing policy) to assist or derail convergence. <a href="https://www.google.com/url?sa=t&amp;source=web&amp;rct=j&amp;opi=89978449&amp;url=https://milescorak.com/wp-content/uploads/2018/12/becker-kominers-murphy-spenkuch-jpe-theory-intergenerational-mobility.pdf&amp;ved=2ahUKEwjupPDz-aSTAxU6a0EAHRyzNBMQFnoECCYQAQ&amp;usg=AOvVaw1SY6TzY7ywRezLcwx7LD6l">Becker's model of intergenerational inequality</a> formalises this, showing that outcomes are path-dependent on both initial genetic endowment and early environmental investments. This is also why there's a strong correlation between holding Abundance-pilled views and being a supporter of open borders, as both policy positions complement each other.</p><p>Regardless of my measured critique, it's abundantly clear that Abundance attracts attacks disproportionately from the low human capital participants in public life, as do attacks on open borders. If this wasn't the case, then why would Elizabeth Warren, a highly intelligent academic, calculate that pandering to somewhat conspiratorial myths that PE is driving up housing costs, will assist her popularity? More generally, the opposition to Abundance seems to be concentrated amongst the hard-leftist base that elected Mamdami, and is driving the Greens to overtake British Labour. Elite human capital theory previously highlighted how educational polarisation makes the centre-left relatively smarter, or at least incentivised not to be too stupid to hold onto the votes of educated people. </p><p>So how do we explain the rising prominence of economic illiteracy as a core focus of centre-left policy agendas, when previously things like rent control were at least marginalised to the fringes? I would argue that educational attainment is distinct from IQ. Their voter base are primarily the dissappointed graduates failing to command a substantial premium, or being economically squeezed. Especially given the likely erosion in the signalling value of many degrees given the expansion in higher education, it's far from obvious that these graduates are even on the right end of the IQ distribution. </p><p>If resentful graduates are indeed the future of leftist and liberal politics, and they succeed in raising the salience and relative status of economic illiteracy, then I fail to see how they're any preferable to the equivalent stupid zero-sum populists on the right. Leftists make us poorer via shackling the planning system, rightists via imposing invisible shackles to free movement. The very fact that neither of these burgeoning coalitions raise the smart critques of Abundance or open borders suggests that one should still support them, even if such support is qualified rather than unequivocal.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><div><hr></div><ol><li><p>Even this likely overstates the costs of expanding high-density metropolitan areas. Despite the favelas, Rio De Janeiro is similarly as picture postcard stunning as Cape Town, as any reasonable observer with good eyesight will conclude.</p></li><li><p>In this case, welfare-improving in the utilitarian sense.</p></li><li><p>I've not put this through ChatGPT yet so lack firm estimates of the welfare calculation, yet the gains from open borders should at least be revised downwards.</p></li><li><p>Yes this is evidence in favour of high heritability estimates, and mostly genetic explanations for observed socioeconomic and behavioural differences between the races. Note that Jones&#8217; work leaves this assumption implicit, via using the IQ estimates derived from Lynn. Nonetheless, these track proxies <a href="https://open.substack.com/pub/microfounded/p/links-for-mid-january-2026?utm_source=share&amp;utm_medium=android&amp;r=56swa">correlate with IQ very well</a>, so Lynn's work (the most comprehensive effort at gathering international data on a crucial variable for everything we care about in the social sciences) is unfairly maligned; mostly by those with a deeply ideological and egalitarian blank-slateist agenda. Likewise, Jones is also notorious for showing that cross-country GDP differences can be accounted for by differences in technology stemming from a millennium ago.</p></li></ol><p></p>]]></content:encoded></item><item><title><![CDATA[March-2026 links]]></title><description><![CDATA[Around 15% of 16-24 year olds in Britain are jobless and not studying.]]></description><link>https://www.ciaranmarshall.co.uk/p/march-2026-links</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/march-2026-links</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Wed, 04 Mar 2026 18:38:25 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<ol><li><p><a href="https://x.com/i/status/2027976558397558972">Around 15% of 16-24 year olds in Britain</a> are jobless and not studying.</p></li><li><p>More confirmation of my demand-side theory of misinformation: the effects of changes to social media algorithms are <a href="https://x.com/i/status/2024565933642014910">not robust</a>. We complain about media bias, yet <a href="https://ijoc.org/index.php/ijoc/article/view/23816">we actively seek it</a>. The market is just providing what the consumers want.</p></li><li><p><a href="https://x.com/i/status/2028027776586965417">These covert tactics</a> remind me of how authoritarian regimes engage in transnational repression.</p></li><li><p>Likewise the notion that <a href="https://marginalrevolution.com/marginalrevolution/2026/03/new-results-on-the-economic-costs-of-climate-change.html">climate change</a> is a looming existential crisis seems inconsistent with people moving to places supposedly at risk of rising sea levels, even without insurance. Implied market activity suggests we're fine. The effects arise slowly, so plenty of time to adapt. Of course adaptation and mitigation decisions feature as costs in these models, yet opportunity costs are everywhere. Should my decision to dine out yesterday be counted as a cost to the cinema industry?</p></li><li><p><a href="https://x.com/i/status/2028044956930056374">Gen Z is embracing sobriety</a> (also I'd like to see these figures adjusted for the Muslim population). Use of most drugs has at least halved, with opiate use almost non-existent. Cocaine and horse tranquilizer use has doubled however, and I'd argue that coke is a substitute to amphetamines. Unlike in America, the market for prescription stimulants like adderall is also almost non-existent here (again charlie is the default).</p></li><li><p>A what point is it established that <a href="https://x.com/i/status/2027542377766834256">Russia is losing badly</a>?</p></li><li><p><a href="https://x.com/i/status/2026983676211319017">Complete pass through in levels may not translate to percentages</a>. It's crucial to get the basic conceptualisations correct.</p></li><li><p>This is <a href="https://x.com/i/status/2027158401210323272">how large the implications of crime policies are</a>. Our leaders can make our communities much safer if they really want to&#8230;</p></li><li><p><a href="https://x.com/i/status/1921388478761521549">It still is Mixue</a>.</p></li><li><p><a href="https://t.co/pwWoPdxXsC">Cool research design</a>. Maybe addiction to the screen is more costly than I thought.</p></li><li><p>We've seem unusually large figures for the economic costs of NIMBYism not withstand replication before, yet <a href="https://x.com/i/status/2025989569976361436https://x.com/i/status/2025989569976361436">even if the effect sizes are much lower</a>, permitting is still a substantial tax on housing.</p></li><li><p>AI is not featuring in the productivity statistics yet due to <a href="https://x.com/i/status/2027127930069897448">slow adoption</a>?</p></li><li><p><a href="https://x.com/i/status/1993936408416055711">Great thread</a> on heart disease. Ageing remains the primary risk factor, and standard pharmacological treatments successfully alleviate the condition. Cholesterol is less of an issue (due to statins), yet obesity and glycemia much more so.</p></li><li><p>Not my field, but what I can gather from <a href="https://www.nature.com/articles/s41586-025-09838-7#ref-CR1">this</a> is that you can improve the scalability of quantum computing by harnessing the properties of spin.</p></li><li><p>The fact that <a href="https://www.ft.com/content/35ff55e1-eed5-4391-8b49-5380f5897f24?shareType=nongift">fertility rates fluctuate over time</a> should give us cause for optimism?</p></li><li><p><a href="https://x.com/i/status/2026671702919241991">The middle gets squeezed once again!</a></p></li><li><p><a href="https://x.com/i/status/2026690425118142685">Ageing is bad for the brain</a>.</p></li><li><p><a href="https://x.com/i/status/2026371561855566122">The latest scapegoat</a> for unaffordable housing amongst the economic illiterates appears to be institutional investors.</p></li><li><p>HDI scores are also very similar <a href="https://x.com/i/status/2026302088423100429">between these countries</a>. Poland has a Southern European standard of living now. A tale in conditional convergence.</p></li><li><p><a href="https://x.com/i/status/2026328546738933780">Gene editing as a means to cure addiction</a>? Never occured to me until now, yet seems rather intuitive in hindsight.</p></li><li><p>Grade inflation: <a href="https://x.com/i/status/2026023711720317116">AI edition?</a></p></li><li><p>Most jobs bundle multiple tasks, some that cannot be automated. In addition, you may need to verify the AI output. <a href="https://x.com/i/status/2025928232856387841">These intra-job frictions affect the substitutability of AI</a> vs human labour.</p></li><li><p>The great awokening was <a href="https://www.hbs.edu/faculty/Pages/item.aspx?num=67359">bad for shareholder returns</a>, which explains in part why it receded. Hopefully the corporate world will learn from this and remain neutral in today's moral panic. </p></li><li><p>Mental health conditions account for a large share of PiP claimants, which is a large factor as to why inactivity is so high here. Hopefully this'll be taken as <a href="https://link.springer.com/article/10.1007/s12207-025-09538-7">a sign to reform</a> the system?</p></li><li><p>"The Nigerian government implemented the Import Substitution Policy". So it's not dependence on external trade that's the root of <a href="https://businessday.ng/real-sector/article/nigerias-industrialization-fails-to-gather-steam-after-65-years/">Nigeria's problems</a>, but rather the usual statism that plagues Africa. Whether rents promote moral hazard amongst elites is a different question altogether though.</p></li><li><p>Buddhism maintains a pacifist reputation in large part due to <a href="https://direct.mit.edu/isec/article-abstract/49/4/119/130813/Monks-Behaving-Badly-Explaining-Buddhist-Violence?redirectedFrom=fulltext">lower coopting of states</a> than other faiths. In general, I do wonder why abrahamic faiths have been so successful at spreading, and cultivating institutional backing, relative to others.</p></li><li><p>About 1/5 of the Spanish population is foreign, yet Spain seems a relatively safe and peaceful country to me, and one of the fastest growing economies in the EU too. If critics of multiculturalism were right, we <a href="https://pablogguz.github.io/blog/pop-projections-esp/">wouldn't expect this</a>.</p></li><li><p><a href="https://x.com/i/status/2025899850965926273">Do ethnic minorities invest more in signalling</a> to compensate for statistical discrimination?</p></li><li><p><a href="https://x.com/i/status/2025697321476907154">Legalise prediction markets everywhere!</a></p></li><li><p><a href="https://x.com/i/status/2025661994578157602">AI is coming for the graduate premium</a> in all the other countries where it holds.</p></li><li><p><a href="https://www.nber.org/papers/w33797#fromrss">For lower-income groups</a>, the college premium has fallen outside the UK too. They're the greatest beneficiaries of gov subsidies for uni education, so I see this as evidence of the signalling channel dominating the human capital channel.</p></li><li><p><a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=6017054">Many authoritarians today deploy decentralised thugs</a> to do their bidding. Colectivos in Venezuela, Wagner and other mercenaries for the Sahel juntas, Putin and international organised crime groups. Does this help promote an image of populist legitimacy?</p></li><li><p><a href="https://x.com/i/status/2011456906691498240">Fantastic work DOGE</a>! Note that entitlements are a large part of why federal spending is so high in the first place.</p></li><li><p><a href="https://x.com/i/status/2024983599158550756">Genome sequencing beats Moore's law</a>.</p></li><li><p><a href="https://x.com/i/status/2024617656515777013">Almost everyone with liver disease either eats or drinks too much</a>. An entirely preventable tragedy with smart lifestyle choices. Don't be one of those people!</p></li><li><p>My theory on this is that social media is causing <a href="https://x.com/i/status/2024204164188840329">less but better matches</a>. Overall, probably a Pareto improvement.</p></li><li><p><a href="https://x.com/i/status/2024503215278993504">Dry counties are becoming a relic of the past</a>. Prohibition is no longer legally sanctioned, yet increasingly voluntarily endorsed.</p></li><li><p><a href="https://www.nber.org/papers/w34157">Yes this matches my priors exactly</a>. The fact that fertility is healthy amongst the Amish, ultra-Orthodox Jews, Mongols, Central Asians, and arguably US conservatives, means humanity will continue. The issue isn't extinction, but slower growth or innovation.</p></li><li><p>I wonder if much diagnostic drift is a function of <a href="https://x.com/i/status/2024157976966091072">diagnosing those with anxiety problems as autistic?</a> So what looks like high-functioning autism might be just social anxiety plus introversion in practice?</p></li><li><p><a href="https://x.com/i/status/2023892029139546243">Testosterone levels have not declined over time.</a></p></li><li><p>No taxation without representation: <a href="https://x.com/i/status/2023034829449675205">democracy started out as a libertarian project</a>.</p></li></ol><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><p></p>]]></content:encoded></item><item><title><![CDATA[In defence of a positive discount rate]]></title><description><![CDATA[After the random and unprovoked battery I recieved by a group of men, in my (usually quiet suburban) neighborhood, I have reflected on the nature of anxiety.]]></description><link>https://www.ciaranmarshall.co.uk/p/in-defence-of-a-positive-discount</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/in-defence-of-a-positive-discount</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Fri, 20 Feb 2026 17:48:01 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<p>After the random and unprovoked battery I recieved by a group of men, in my (usually quiet suburban) neighborhood, I have reflected on the nature of anxiety. My anxiety level, elevated in the wake of the ambush, has now receded to its norm. Yet the fact that anxiety spikes AFTER the distressing event has already occurred, rather than before, suggests it's an irrational and useless phenomenon. If anxiety was protective throughout our evolution, then why do we feel fine until danger strikes? If anxiety helps us avoid danger, then this pattern is suboptimal.</p><p>Perhaps I am confusing anxiety, anticipation of harm or a negative future shock, with adrenaline. Very likely, the surge in levels of this hormone was necessary to hedge against pain from aches, and to promote a swift recovery. Yet it's precisely norepinephrine that's responsible for our endogenous &#8220;fight or flight&#8221; behaviours that characterise anxiety. Without this neurotransmitter, you cannot feel anxiety, although the reverse isn't true.</p><p>If this ex-post transitory surge in acute anxiety was linked to a meaningful change in the posterior probability of an adverse shock, then it can be justified. Yet you're much more likely to be harmed by crossing the road, or a car accident, than a random violent crime. You're much more likely to be a victim of violent crime on a booze-filled night out in a vibrant city-centre bar than on a quiet suburban street. Yet I engage in these activities on a regular basis, without any obvious hesitation. If anxiety was rational, these events rather than walking the streets alone should be more troublesome, yet my emotional concern is for the latter.</p><p>Therefore, anxiety is a profoundly irrational phenomenon uncorrelated with risk with little predictive power. Such biases are costly however, so rational agents seek to minimise them [1]. How does this apply to anxiety? Obviously, humanity's favourite intoxicant is consumed for this very purpose. The main mechanism via which alcohol produces euphoria is via reducing anxiety [2].</p><p>However, even abstracting from the rebound and alcohol's potential for physical or psychological dependence, I posit that <em>the lifetime costs of any alcohol consumption always outweigh its gains</em>. Fundamentally, alcohol is a depressant, thereby it hampers cognition. Given the importance of human capital both to individual <a href="https://open.substack.com/pub/microfounded/p/a-primer-on-economic-growth?utm_source=share&amp;utm_medium=android&amp;r=56swa">and societal outcomes</a> [3], this is not insignificant. Suppose we consider IQ as a constraint in a two-period model. In the first period, you can spend some points on getting drunk, or keep the points and invest in higher lifetime wealth (doing a productive activity). Next period, if you got drunk, your IQ returns to baseline. If you remained sober however, your lifetime wealth increases. Assume that wealth is utility, and you would be better off if you stayed on the wagon [4].</p><p>When we drink, we are in effect borrowing from our future utilities to increase our present utility. However, just as we borrow to finance purchases unaffordable to us with our present incomes alone, this borrowing is rational and justified. If we feel irrational anxiety, or any other temporary state of negative affect, and we borrow from a happier future, then this promotes our rationality. Just as with regular borrowing where you're broke if you rely on this, your mental and physical health (therefore your human capital) is depleted if you rely on liquor. Nonetheless, we don't condemn debt on the basis that some irresponsible individuals end up bankrupt, so neither should we condemn drinking or any other activity in which a positive discount rate is involved. Consider time discounting as the <em>intertemporal substitution of utilities</em>.</p><p>My conception of time discounting as intertemporal substitution makes sense once you consider <a href="https://chatgpt.com/share/699896cf-8b18-800a-903e-ad61d30bb6ab">how you distinguish time preference from intertemporal consumption</a>. Credit constraints render a bias towards present consumption obvious, yet why should we call one intertemporal substitution along a utility function, and the other time preference, just because of one constraint? Empirically, you're generally unaware of one's financial situation, so you cannot easily make this distinction. Sure, HANK modelling is more structurally identified due to this separation, yet this is precisely what I called mathematical sophistry to fit the data. Ontologically, I think both are just different means to state the same thing, that we hold preferences relating to time and when we want to consume. </p><p>Perhaps models that do not explicitly microfound this as an intertemporal tradeoff, or require an extra parameter for discounting to fit the data, are bad models. Yet dynamic game theory relies on time discounting. Positively, discard the discount rate, and we lose many insights regarding how and why agents cooperate. Normatively, any weighting of the future less than the present could be considered as undermining growth via reducing physical and human capital accumulation. Yet it's plausible that recessions cause scarring. More present-minded individuals yield higher mpcs, and their discounting of future taxes undermines Ricardian equivalence. This myopia should aid a fiscal stimulus, so aid recovery, hence mitigate scarring. As such, it's not obvious that a positive discount rate is necessarily damaging for future prosperity once one considers carefully the dynamics, although a model is probably required.</p><p>Despite my defence of positive discount rates, both positively and normatively, this phenomenon is also associated with many of our worst pathologies and impulses (including my attack!). History demonstrates that we cannot take the existence of a stable civilisation for granted. Excessive time discounting is obviously pernicious.</p><p>Is there an optimal discount rate, and if so, what value does it take? I tend to consider discount rates as the opportunity cost of investment, as if I recieve a smaller sum now in lieu of a larger future sum, I can invest it into the capital markets. In our standard models, this return is the marginal product of capital - equivalent to the risk-free rate. In more complicated models of capital and asset heterogeneity, there are numerous returns that differ according to risk. Indeed, this explains how impatience tends to be correlated with risk-seeking, and if discounting was a bias (as most psychologists think) then we'd expect this to be uncorrelated with risk preference. One might also augment future returns via weighting with the probabilities of existential risk events, which may generate nonlinearities and hyperbolic discounting.</p><p>In principle, one can select a portfolio of returns, consistent with one's risk preferences, to match their discount rate. Yet this is not an arbitrary allocation, as not all values of return are possible. It appears that most, at least some of the time, discount at rates far in excess of what can be justified via returns in the capital markets. As a result, it's tempting to argue that we should place higher value on future periods than we currently do. Most versions of virtue ethics seek precisely to do this, whilst embedding our imperfections (so realising a rate of zero is unfeasible). However, we must seriously consider the possibility that a rational agent holds information regarding their own life and the relevant probabilities of future catastrophies that we don&#8217;t have access to. In any case, with much of medical science p-hacked to death, it&#8217;s unclear how we could live in a manner consistent with lower discounting even if we should or wanted to. Therefore, we should be incredibly suspicious of all paternalistic attempts to change our lifestyles, and not discount our individual rationality.</p><div class="subscription-widget-wrap-editor" data-attrs="{&quot;url&quot;:&quot;https://www.ciaranmarshall.co.uk/subscribe?&quot;,&quot;text&quot;:&quot;Subscribe&quot;,&quot;language&quot;:&quot;en&quot;}" data-component-name="SubscribeWidgetToDOM"><div class="subscription-widget show-subscribe"><div class="preamble"><p class="cta-caption">Thanks for reading Microfounded! Subscribe for free to receive new posts and support my work.</p></div><form class="subscription-widget-subscribe"><input type="email" class="email-input" name="email" placeholder="Type your email&#8230;" tabindex="-1"><input type="submit" class="button primary" value="Subscribe"><div class="fake-input-wrapper"><div class="fake-input"></div><div class="fake-button"></div></div></form></div></div><div><hr></div><ol><li><p>I like this framing of the expectations operator <a href="https://x.com/i/status/2008945859778494916">as a loss minimiser</a> of forecasting errors. Of course such exist, and cognitive bias can produce them, yet over time agents learn. There's no reason to expect errors to be correlated, or cognitive bias to produce correlated errors, so the use of this operator is justified <a href="https://open.substack.com/pub/microfounded/p/yes-partisan-bias-in-forecasting?utm_source=share&amp;utm_medium=android&amp;r=56swa">and rationality results</a>. I think this is <a href="https://open.substack.com/pub/microfounded/p/in-praise-of-hedonism?utm_source=share&amp;utm_medium=android&amp;r=56swa">how we can square the standard rational choice framework with behavioural economics</a>: rationality arises as we actively minimise our errors.</p></li><li><p>Albeit the mechanism focuses more on stimulating GABA so reducing inhibition, as opposed to suppressing norepinephrine per se. There are also notable increases in dopamine, serotonin, and endorphins, although I consider this a by-product of reduced anxiety.</p></li><li><p>Although I'm increasingly sceptical of models that imply that any investment into human capital always increases growth permanently. If that was the case, then it would be optimal to devote all resources to human capital. Such a conclusion denies the salient role of tradeoffs or opportunity costs, which is a fatal flaw for an econonic theory. Nonetheless, the returns to investing in human capital are positive, which is the main factor in this analysis.</p></li><li><p>Of course this is a highly simplistic framwork. What good is wealth for in a world devoid of pleasure, fun and convivality right? I'd argue that other intoxicants can promote cognition, via expanding one's set of perceptions or for (especially with stimulants) nootropic value. As for socialisation, vital for information aggregation so cognition and human capital, our culture of drinking indeed serves as a focal point. Yet this focal point is inefficient: as I've substantially moderated my consumption, I've noticed that much of what we consider socialisation is merely ritualistic bonding. How many conversations are good enough to learn from at a party, or even your median pub? I think the Bay Area rationalist culture of sober socialisation is far superior in this regard.</p></li></ol><p></p>]]></content:encoded></item><item><title><![CDATA[Mid-February 2026 links]]></title><description><![CDATA[One of the main bottlenecks to AGI is that tasks can't easily be decomposed. AI may substitute or complement some elements of a task but not others, or adoption may change overall composition of a task. Hence why we have the nascent literature modelling the diffusion of AI]]></description><link>https://www.ciaranmarshall.co.uk/p/mid-february-2026-links</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/mid-february-2026-links</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Thu, 19 Feb 2026 21:19:23 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<ol><li><p>One of the main bottlenecks to AGI is that <a href="https://x.com/i/status/2021038215667515559">tasks can't easily be decomposed</a>. AI may substitute or complement some elements of a task but not others, or adoption may change overall composition of a task. Hence why we have the nascent literature <a href="https://arxiv.org/abs/2602.11865">modelling the diffusion of AI</a> across multiple sectors or tasks.</p></li><li><p>The British IPP was actually good sentencing policy. <a href="https://x.com/i/status/2023177739369603253">Locking up recidivists indefinitely could halve crime</a>. We should bring it back!</p></li><li><p><a href="https://x.com/i/status/2023167778006434108">Beware of observational studies</a>, and the word &#8220;associated&#8221;, as it often just means linear regression with controls.</p></li><li><p><a href="https://x.com/i/status/1874048712512856233">Is peer review culpable</a> for the TFP decline of 1980s-2020s?</p></li><li><p>Assume that 3% of the US and UK population are users (reported use + 1pp to account for underreporting). We know that <a href="https://www.google.com/url?sa=t&amp;source=web&amp;rct=j&amp;opi=89978449&amp;url=https://www.globaldrugsurvey.com/wp-content/themes/globaldrugsurvey/results/GDS2019-Exec-Summary.pdf&amp;ved=2ahUKEwiTzc-TreaSAxWDT0EAHXaTLuUQFnoECFwQAQ&amp;usg=AOvVaw3jUuI1dbKAUPnDUUnZ_CgY">cocaine comsumption tends to be bimodal</a>, with the <a href="https://www.google.com/url?sa=t&amp;source=web&amp;rct=j&amp;opi=89978449&amp;url=https://pmc.ncbi.nlm.nih.gov/articles/PMC3533010/&amp;ved=2ahUKEwiTzc-TreaSAxWDT0EAHXaTLuUQFnoECCcQAQ&amp;usg=AOvVaw3I1yrUXgchuBYs0_uAbwQW">vast majority using infrequently</a>, and a large subset using every weekend or so. So take these top 10% of users, and the probability of overdose (which cumulates over lifetime, and appears to be <a href="https://www.nber.org/papers/w34788">rising with rising purity and supply</a>) could be as high as 1% per year. I didn't know that cocaine overdose was that salient.</p></li><li><p>Mass deportations actually <a href="https://www.nber.org/papers/w34788">reduce wages</a>, and result in <a href="https://www.nber.org/papers/w34791">more deaths</a>.</p></li><li><p><a href="https://x.com/i/status/2022022860706103780">A healthier alternative to booze?</a> I'll report back on the results.</p></li><li><p><a href="https://x.com/i/status/2021968731346518359">I like this analogy to manifolds</a>. AI is capable of harnessing enough data to compete with structural models though, and of course is adept at structural identification. All of this is relevant for whether the Lucas Critique still holds today.</p></li><li><p>&#8220;We can just do things&#8221;, <a href="https://x.com/i/status/2021828823076237453">malaria and dengue edition</a>.</p></li><li><p><a href="https://x.com/i/status/2021334583158112300">Another example of this</a> is the alliance of &#8220;beltway libertarians&#8221; with elite human capital, which helps to explain why libertarianism carries such disproportionate policy influence relative to its popularity (as well as it being correct on normative questions of course ;). I hope that the <a href="https://open.substack.com/pub/richardhanania/p/thoughts-on-elite-versus-populist?utm_source=share&amp;utm_medium=android&amp;r=56swa">conspiratorial and populist turn</a> in the movement doesn&#8217;t undermine this, although arguably <a href="https://x.com/i/status/2021353623247323424">intelligence matters more than ideology these days</a>.</p></li><li><p><a href="https://x.com/i/status/2021311595146604679">Social mobility in the Nordics</a>: where stereotypes do not match reality.</p></li><li><p>&#8220;<a href="https://x.com/i/status/2021386894076981653">Another study finds no mental health benefits of cellphone bans</a>&#8221;.</p></li><li><p><a href="https://x.com/i/status/2021381825495773593">How economics shapes architecture</a>.</p></li><li><p><a href="https://x.com/i/status/2020861872002482400">The Japanese government's net worth</a>, improving, is a lot better than it's debt/GDP suggests.</p></li><li><p>The main lesson from <a href="https://www.nber.org/papers/w34722">this</a> appears to be that labour-augmenting technology can offset diminishing marginal returns to capital accumulation.</p></li><li><p><a href="https://t.co/04x84V6UOF">A good up-to-date primer</a> on the state of AI safety research.</p></li><li><p>Seems like the one-child policy was just the <a href="https://direct.mit.edu/rest/article-abstract/doi/10.1162/REST.a.1695/135194/The-Limits-and-Consequences-of-Population-Policy?redirectedFrom=fulltext">tip of the iceberg</a>.</p></li><li><p><a href="https://x.com/i/status/2019233120432566555">Well deserved</a> - the Young Lion Resting is a masterpiece of realism.</p></li><li><p><a href="https://x.com/i/status/2019078989348774129">Are hallucinated cases good law?</a></p></li><li><p>Eliminating all cancers "would add between 2 and 3 years to life expectancy. But since the median age of a cancer diagnosis is 66, the same patients would anyway soon be diagnosed with another manifestation of aging &#8212; like Parkinson&#8217;s, hypertension, severe illness from an otherwise mild infection, or a broken rib". Yet "the United States spends a mere 0.54% of its National Institutes of Health research budget on the biology of aging". We need to <a href="https://silverlinings.bio/?chapter=present">increase funding for anti-ageing research</a>.</p></li><li><p><a href="https://x.com/i/status/2019081857305100627">Tau appears to be the most predictive symptom of Alzheimer's</a>.</p></li><li><p><a href="https://x.com/i/status/2019444487093624891">Price theory propaganda!</a></p></li><li><p><a href="https://x.com/i/status/2018805595734700112">How AI can actually fight polarization and misinformation</a>. Also it costs money to use Claude Code, so (unlike previously) the marginal cost of misinformation production with AI is positively-sloped, albeit autonomous agents could be potent vectors.</p></li><li><p><a href="https://x.com/i/status/2018436050935292276">A new side-hustle?</a></p></li><li><p><a href="https://x.com/i/status/2017479930364498371">Good sleep is vital for cognition</a>, even if you do feel okay with four hours.</p></li><li><p>Beliefs are endogenous. Negative affect is rising in part as <a href="https://x.com/i/status/2018006505455329641">we're incentivising anxiety and depression.</a></p></li><li><p><a href="https://x.com/i/status/2018020260335493547">Alignment is an institutional-level problem</a> with some emergence, so individual firms or (to borrow from Hayek) social planners are not fully equipped to know how to solve this. My experience of intensive LLM use so far though is that, by following its recommendations, I've behaved more prosocially.</p></li><li><p>Yeah a politics rooted in zero-sum tribalism is <a href="https://x.com/i/status/2017786655009071286">personality rather than ideologically grounded</a>.</p></li><li><p><a href="https://x.com/i/status/2017991428077498445">If this model is true</a>, then in democracies there is mean-reversion after a period of populist rule to technocratic governments. This could explain why democracies perform better economically than autocracies. I also like the idea that initially, populists appoint technocrats to key cabinet roles as a credible commitment device for investors, which explains Trump's first term. As populism becomes more institutionally entrenched however, they become more radical as they erode checks and balances.</p></li></ol><p></p>]]></content:encoded></item><item><title><![CDATA[February 2026 links]]></title><description><![CDATA[Heritability of lifespan doubles once accounting for extrinsic mortality, yet extrinsic mortality itself is correlated with traits that also likely reduce lifespan, such as risk taking or low conscientiousness.]]></description><link>https://www.ciaranmarshall.co.uk/p/february-2026-links</link><guid isPermaLink="false">https://www.ciaranmarshall.co.uk/p/february-2026-links</guid><dc:creator><![CDATA[Ciaran]]></dc:creator><pubDate>Tue, 03 Feb 2026 19:24:48 GMT</pubDate><enclosure url="https://substackcdn.com/image/fetch/$s_!zoHy!,w_256,c_limit,f_auto,q_auto:good,fl_progressive:steep/https%3A%2F%2Fsubstack-post-media.s3.amazonaws.com%2Fpublic%2Fimages%2F50e924fe-62bb-4918-a374-7a949e7d8d04_680x680.png" length="0" type="image/jpeg"/><content:encoded><![CDATA[<ol><li><p><a href="https://x.com/i/status/2016990009635602434">Heritability of lifespan doubles once accounting for extrinsic mortality</a>, yet extrinsic mortality itself is correlated with traits that also likely reduce lifespan, such as risk taking or low conscientiousness. To set the goal of, and implementing the (often arduous) lifestyle practices of extending longevity, you almost certainly meet some minimum threshold for conscientiousness in the first place.</p></li><li><p>Anti-vaxxers are creating <a href="https://x.com/i/status/2016217002008809982">gargantuan negative externalities</a> for the rest of us. My most authoritarian idea is that I'm open to compulsory vaccinations. At the very least, vaccine mandates for public spaces such as schools, and private businesses being allowed to implement such, are of course justified.</p></li><li><p><a href="https://x.com/i/status/2016607658271281642">RIP</a></p></li><li><p><a href="https://x.com/i/status/2015881473060991405">Why Japan's massive public debt is sustainable.</a></p></li><li><p><a href="https://x.com/i/status/2015859422417870858">So to be clear,</a> the link between social media use and mental health amongst young people is ambiguous at best (except perhaps for young liberal or adolescent females, where the case for a link is stronger). Bullying, suicide, substance abuse, delinquency, and dropout rates peaked in the 70s and 80s - inconsistent with the notion that social media is generating a teen mental health crisis. Policymakers, authoritarian safetyists, and enemies of free speech are using this incredibly tenuous nascent &#8220;research&#8221; on the mental health impacts of social media to implement bans for specific age groups. Of course, as in Britain us adults have to undergo age verification (with biometric readings and official documentation) just to read Substack articles, these bans will restrict free expression for all of us.</p></li><li><p><a href="https://www.pnas.org/doi/10.1073/pnas.2415126122">IQ and conscientiousness matter in sports too</a>. Neuroticism and agreeableness are negatively correlated with success here, whilst openness to experience and extroversion are positively correlated.</p></li><li><p><a href="https://www.nber.org/papers/w34749">21st century fertility decline in Latin America</a> "is driven primarily by reductions in within-group birth rates rather than by changes in population composition". Delayed childbirth and those with kids having less, rather than childlessness, are the main explanations.</p></li><li><p>Attitudes to immigration are, in part, influenced via <a href="https://onlinelibrary.wiley.com/doi/epdf/10.1111/ssqu.12891">predicted partisan support of the newcomers</a>. Nonetheless, racial prejudice is also a variable with partisan variation&#8230;</p></li><li><p>The US government is basically <a href="https://x.com/i/status/2015515105761354144">a welfare state with a military and police force attached</a>. Social spending merely stabilised, rather than fell, <a href="https://x.com/i/status/2015530562715357387">throughout the &#8220;neoliberal&#8221; era</a>. By expenditures as a proportion of output, this makes the US <a href="https://x.com/i/status/1962931182586184003">the largest welfare state in the developed world</a> - outpacing even the Nordics! However, as <a href="https://x.com/i/status/2014820123970859365">this welfare state is largely gerontrocratic</a>, it's not associated with redustributive vibes.</p></li><li><p>Why it's <a href="https://x.com/i/status/2014666448669487117">very rare to have both cancer and Alzheimers</a>.</p></li><li><p>What I find fascinating <a href="https://nymag.com/strategist/article/cheap-vs-expensive-jeans.html">about jeans</a> is that they owe their immense popularity to one film. If the media landscape can cause such durable change in tastes, then this substantially increases my estimates of the social costs of social media misinformation.</p></li><li><p><a href="https://phys.org/news/2025-12-universe-lopsided.html">How cosmic dipole anomalies pose a challenge to &#955;-CDM</a>. Even in a field where significance is reported in &#963;s rather than p-values, there's immense gaps and disagreements in our knowledge, which implies we should never be too confident on anything.</p></li><li><p><a href="https://www.nature.com/articles/d41586-026-00177-9?utm_source=x&amp;utm_medium=social&amp;utm_campaign=nature&amp;linkId=41690587">Quantum superposition can work with thousands of atoms</a>. This could make quantum computing commercially viable at scale.</p></li><li><p>With AI, you get <a href="https://www.nber.org/papers/w34713">the best predictive results</a> if you start with structural priors then fine-tune with real-time data. Not a complete abandonment of the Lucas critique, yet this does indeed suggest a role for adding on extra parameters.</p></li><li><p><a href="https://x.com/i/status/2014060163792097281">A short thread</a> on how government funding of select public goods (innovation is nonrival, and may or may not be excludable depending on IP etc, so is considered a semi public good) can be optimal. Although many of these cases (science, biotechnology, nuclear, etc) yield obvious military implications, so it&#8217;s unclear whether strict deontological minarchists should by their own standards even be opposed to this.</p></li><li><p>Affirmative action or DEI-consciousness in hiring decisions does indeed <a href="https://x.com/i/status/2013778721333821496">boost the career prospects of minorities</a>. When I speak to proponents of such schemes, they nearly always justify them on the basis of equality of opportunity (a value actually consistent with meritocracy), and indeed if human capital accumulation is subject to learning-by-doing dynamics (generating increasing returns), then there exists path dependency. On the other hand, human capital <a href="https://open.substack.com/pub/microfounded/p/a-primer-on-economic-growth?utm_source=share&amp;utm_medium=android&amp;r=56swa">could easily be subject to diminishing marginal returns too</a>. If the latter is correct, then there are limits with respect to the extent that DEI can increase minority capital.</p></li><li><p><a href="https://x.com/i/status/2013409235803988028">Optimism</a> <a href="https://x.com/i/status/2013357742560272712">on American</a> <a href="https://x.com/i/status/2013397687240962347">fertility</a>.</p></li><li><p><a href="https://x.com/i/status/2013663661785481299">Deregulation of the airlines is a major win</a> for proponents of free markets.</p></li><li><p>"<a href="https://www.nber.org/papers/w34705">AI exposure and adaptive capacity are positively correlated</a>".</p></li><li><p><a href="https://www.nber.org/papers/w34699">Is the prevalence of labour-market monopsony overestimated?</a></p></li><li><p><a href="https://x.com/i/status/2013283645696463198">Against Autor et al (2013).</a></p></li><li><p><a href="https://x.com/i/status/2013261344082968867">China has risen to the technology frontier</a>.</p></li><li><p><a href="https://x.com/i/status/2013276229831369157">Gupta reckons that the Internet is connected to fertility decline</a>, via raising the value of outside options to sex or childrearing. However, the Internet also (via online dating) reduces transaction costs to matching, and may also allow for more efficient matches. We must model the effects of the Internet in general equilibrium.</p></li><li><p>"<a href="https://www.nber.org/papers/w33818#fromrss">Most presidential ads were targeted toward parties&#8217; own supporters</a>". "No detectable effects of removing political ads on political knowledge, polarization", and so social media isn't the main problem. The demand for misinformation and tribalism dominates, although social media does drive the fixed and marginal costs of misinformation production down to near-zero, which obviously increases its spread so is an issue.</p></li><li><p><a href="https://x.com/i/status/2013179969489297510">The evidence for the harms of microplastics is very weak</a>.</p></li><li><p>LP(a) increases your risk of cardiovascular disease, and unfortunately <a href="https://x.com/i/status/1961084474122252640">its variation across humans is entirely genetic</a>. Fortunately, we may be on the verge of treatments for this.</p></li><li><p><a href="https://x.com/i/status/2012604979064815943">Peak muscular strength occurs within the late 20s</a>.</p></li><li><p>Out of the <a href="https://x.com/i/status/2012879225519489352">very tiny proportion of ballots marked as fraudulent</a>, most of those were marked by mistake&#8230;</p></li><li><p><a href="https://x.com/i/status/2011614079027392907">Time spent childrearing</a> amongst couples with children has increased over the last few decades.</p></li><li><p><a href="https://papers.ssrn.com/sol3/papers.cfm?abstract_id=6051694">Another dynamic structural model</a> on the effects of AI on wages, output, and employment. Ambiguity noted in the labour-market response. Whether AI is a substitute and complement is task-dependent, and changes over time.</p></li></ol><p></p>]]></content:encoded></item></channel></rss>