Advertise on podcast: Astral Codex Ten Podcast

Finalist #8 in the Book Review Contest This is one of the finalists in the 2026 book review contest, written by an ACX reader who will remain anonymous until after voting is done. I'll be posting about one of these a week for several months. When you've read them all, I'll ask you to vote for a favorite, so remember which ones you liked] [Content warning: Sexual and relationship practices from a thousand years ago, from a time and place with a very different morality than what you probably subscribe to.] The past is an alien civilisation Around the year 1000, the Imperial Court of Japan in Kyoto was a world of opulence, aesthetics, and ambition. Isolated from the lives of regular commoners, every aspect of the lives of the elite were governed by complex etiquette rules, and relationships were thoroughly intertwined with politics and the ambition for power and wealth. High-ranking women and men lived lives so separate that they might have a passionate love affair without properly seeing each other's faces. It was in this world that Murasaki Shikibu, an intelligent and educated lady in Empress Shōshi's court, wrote The Tale of Genji, which is widely considered to be the world's oldest novel. It is an extraordinary masterpiece and a highly questionable soap opera, and I've never read anything like it. https://www.astralcodexten.com/p/your-book-review-the-tale-of-genji

I am Daniel Böttger1. In 2023, my review of On The Marble Cliffs took second in the ACX book review contest, and Scott offered me the right to pitch him more essays. I have worked as a neuroscientist, so in 2024 I pitched a post with my theory of consciousness. Later that year, my connection to neuroscience took an unexpected turn, and I wrote about my experience getting diagnosed with brain cancer. This post is an update on how I'm doing. I'm doing well. Very well, in fact. Suspiciously well. So well that the only other person I've ever heard of doing as well as I am was Jo Cameron, who was profiled on ACX for her rare genetic mutation that makes her incapable of negative emotion. My case can't be a mutation, so it must be related to my brain cancer and subsequent surgery. I write about it here in the hopes of making a novel contribution to the study of low-suffering phenotypes. Content warning: the first part of this review contains medical details that some people might find gruesome; I am bad at judging these things since I can no longer feel disgust or fear myself, and have tried to err on the side of completeness. https://www.astralcodexten.com/p/absurd-adventure-and-amygdalectomy

I. Econblogger Nicholas Decker is not a fan of AI 2040: One of the centerpieces of AI 2040 is the proposal that we pause the development of AI at a high level, use the AI to research alignment, and only then proceed. I am skeptical of this, and not only because it seems impractical to get such cooperation. My first argument is that I do not believe a period of "researching alignment" is meaningful – alignment research is simply capabilities research, patching particular bugs in the system, and we're not going to find anything deep without actually being in contact with the systems […] I envision AI alignment as being like research into aviation safety. There is no grand theory of why airplanes crash, unless you take that to mean gravity. Instead, we patch little problems. The airplane crashed because of metal fatigue in the engine – okay, we mandate inspections of engines, and prevent crashes from occurring by that source. As new problems arise, we iterate. We don't even need for there to be a crash to make improvements – we test proactively, we build in redundancy, and we monitor for deviations which could be a threat. What we are not doing is thinking about how we are going to keep flying saucers from crashing. If flying saucers are invented, then we will work to keep them from crashing, but we will use exactly the same methods. We will test them, see how they perform, and patch particular problems. AI will be the same way […] We should expect alignment to happen by default. My challenge for Nicholas is: would this work on you? https://www.astralcodexten.com/p/nicholas-decker-in-hell

Finalist #7 in the Book Review Contest [This is one of the finalists in the 2026 book review contest, written by an ACX reader who will remain anonymous until after voting is done. I'll be posting about one of these a week for several months. When you've read them all, I'll ask you to vote for a favorite, so remember which ones you liked] This is not a review of Rabelais. This is a review of a certain, incomplete translation of Rabelais. It is also arguably one of the greatest translations in our language. Let's meet the hero of our story. https://www.astralcodexten.com/p/your-book-review-thomas-urquharts

[Original post: Why I'm Staying Out Of The Substack Religion Debate] Ben Smith writes: This post sure reads like participating in the object level debate, not just "writing a post about how I won't participate". I did joke about this at the end, but I also want to defend calling this a post about how I won't participate. This essay presented a kind of hand-wavey heuristic for why I'm not spending lots of time examining the details of every individual argument. This is fine, everyone has to do this or be overwhelmed, but I think it's important to keep hand-wavey heuristics for not participating in arguments, vs. actual participation in arguments, distinct. Little annoys me more than when I spend weeks carefully gathering citations and making a substantive contribution in a domain, and somebody responds with "well that's obviously all b******t because it vaguely reminds me of something I have negative affect towards". It's not necessarily wrong to deprioritize a topic because it vaguely reminds you of something that you have negative affect toward, but I would prefer these people admit they're dismissing/ignoring it rather than claim to be engaging with it. I'm working on a longer post about this topic. https://www.astralcodexten.com/p/highlights-from-the-comments-on-the-491

In early July, Cassie Pritchard argued on Twitter that liberalism had failed; it bet the farm on economic progress making people happier, but although it delivered impressive economic progress, happiness had failed to follow. In late July, I countered that Pritchard had made a mistake by comparing happiness to income, when the literature instead supports a correlation of happiness with log(income). Add the log term, and most happiness-income relationships reappear, and liberalism goes back to looking pretty good. Last week, Pritchard responded on her Substack. I don't have the interest to give this the full treatment it requires, but she deserves some response, so I'll make a few points. https://www.astralcodexten.com/p/re-re-re-pritchard-on-liberal-happiness

[This is one of the finalists in the 2026 book review contest, written by an ACX reader who will remain anonymous until after voting is done. I'll be posting about one of these a week for several months. When you've read them all, I'll ask you to vote for a favorite, so remember which ones you liked] 1. A New Cause Area In October 1819, my grandmother's grandfather's grandfather, Hiram Bingham I, stood with his wife, Sybil, and his friends outside Park Street Church in Boston and bade farewell to family before venturing into the unknown. They would spend the next five months on a cramped ship sailing to a foreign land of strange people, full of "destitution, degradation, and barbarism." They did not know if they would ever return to America. Unlike others who voyaged out to sea, they were not whalers, nor merchants trying to make a quick profit. Instead, their goal was far more ambitious: to uplift an entire nation out of heathenry to civilization. Or as Hiram wrote, to "most effectually and most extensively promote the Redeemer's cause with the means that are put into our hands". I first came across Hiram's memoir, A Residence of Twenty-One Years in the Sandwich Islands, on my honeymoon to the Hawaiian Islands last summer. I had vague knowledge of a family connection to the area, and decided to do some research into it. As I started reading, I had a growing sense of deja vu as I recognized my own patterns of thinking in Hiram's words. Today's Effective Altruists sincerely want to do the most good possible, and often focus on international development as a means of improving lives. However, there is another group who fits that description equally well: 19th-century missionaries. Hiram and his colleagues believed that Heaven and Hell were not metaphorical, and that doing the most good meant saving the most souls from eternal torment. And what, they asked themselves, was the most effective means towards accomplishing this goal? Spreading the Gospel to those who had never heard it. All of humanity required salvation, and those who lived in foreign lands mattered just as much as those who lived nearby. As a missionary destination, the Hawaiian Islands (then known as the Sandwich Islands), had several compelling advantages. First, the islands were very neglected, being recently discovered. While not as important as China, Egypt/Palestine, or India, they still held a sizable population. And unlike those places, there was little competition from other missionaries or pre-existing organized religions, making them much more tractable for conversion. The mission to Hawaii would prove notably cost-effective compared to other missions1. Basically all that was needed was a ship, a printing press, and missionaries to teach the Bible. In other words, if the EA Forum existed in the early 19th century, I could easily imagine a post arguing that bringing the Gospel to the Sandwich Islands is a promising cause area. So, with the benefit of 200 years of hindsight, what can Effective Altruists and other aspiring do-gooders today learn from the previous wave of people who wanted to save the world? https://www.astralcodexten.com/p/your-book-review-a-residence-of-21

I. Matthew Adelstein (aka Bentham's Bulldog) and Richard Chappell debate the existence of God. So do JP Andrew, Benjamin Tettu, Sangwon Lee, Ethan Muse, other Ethan, and "Atheistic Journals", all within this month! I thought the omnipresence of the early '00s online atheism debate was a time-bound historical phenomenon. But now that the blogosphere has reincarnated as Substack, it's back, nearly as strong as ever. I enjoyed participated in the early 00's version, but the current incarnation leaves me cold. I can't get as interested as I once did in the details of the Fine-Tuning Argument, the Argument From Miracles, et cetera. It's not just that I've already served my time in the theology mines. My lack of belief in God intuitively feels like it precedes all of these things. Consider by analogy a society where people regularly debated whether aliens assisted the rise of Napoleon. There are many reasons to believe in such assistance: Napoleon's rise from Corsican nobody to Emperor and would-be world conqueror was a bizarre deviation from the usual pattern of history. He won battles outnumbered 4-to-1, when everyone knows victory usually goes to the larger army. He became monarch of France immediately after it had declared eternal enmity against the concept of monarchy and resolved to murder anyone who didn't hate monarchy enough. And the arguments against such intervention are comparatively flimsy. True, nobody saw aliens, but a sufficiently advanced civilization could conduct its interventions in secret. True, our prior for alien intervention is generally low, but maybe this is unjustified: we have no idea how many historical events the aliens have intervened in; Alexander the Great was pretty strange too. True, Napoleon finally lost, but this is not decisive; maybe the aliens only wanted him to blaze brightly for a few years before his eventual defeat, or maybe stronger aliens were backing the Duke of Wellington. In a world where this hypothesis somehow entered the space of serious debate, it would be hard to dislodge. Our own historical community is protected from it not because they can precisely add up the Bayesian evidence for and against each of these considerations and conclude its falsehood, but because common sense precludes entertaining it in the first place. This isn't to say that Reason doesn't work - if someone could precisely add up the Bayesian evidence for and against these considerations, they would get the right answer - but as a historical matter, this type of delicate reasoning wasn't how our society resolved this question. My atheism is more deeply rooted in whatever prevented us from considering this question in the first place than in the type of delicate reasoning that could get us out of it. https://www.astralcodexten.com/p/why-im-staying-out-of-the-substack

[This is one of the finalists in the 2026 book review contest, written by an ACX reader who will remain anonymous until after voting is done. I'll be posting about one of these a week for several months. When you've read them all, I'll ask you to vote for a favorite, so remember which ones you liked] Holocaust stories, both true and fictional, tend to repeat the same few clichés over and over. There's the innocent child who only partially understands what's happening (Diary of Anne Frank, Boy in the Striped Pajamas). There's the sentimental redemption story that focuses on a small individual act (Life is Beautiful, The Book Thief). And of course, there's the good German, or at least the morally conflicted one (Schindler's List, The Reader). You won't find any of these tropes in The Escape Artist. This 2022 book by Jonathan Freedland1 tells the true, and largely unknown, story of one of the few Jews ever to break out of Auschwitz. The details of his improbable escape are remarkable enough, but what really makes the story fascinating is the way it so thoroughly defies every single expectation we have of a Holocaust narrative. Its deeply unlikeable protagonist eventually alienates every friend and supporter he has, and dies a bitter old man, almost completely forgotten by history. His story lacks not only good Germans, but even good non-Germans, with his harshest criticism saved not for the Nazis, not even for the dithering Allies, but for the Jewish leaders of Europe. And though one could see the story of his escape as a triumph, in his own telling, it's a failure, for although he makes it out of Auschwitz against all odds, he fails at his larger mission: to stop the Holocaust. There's no redemption here, no moral uplift, no lessons save for perhaps the grimmest and most nihilistic "lesson" I've ever encountered in any story, Holocaust-related or otherwise: that when confronted with the unthinkable, most people's natural tendency is denial. But we're getting ahead of ourselves. To get out of Auschwitz, first you have to get into Auschwitz… https://www.astralcodexten.com/p/your-book-review-the-escape-artist

Since the beginning of time, mankind has yearned to drink a cup of coffee at 5 PM and go to sleep at 10. But now there's an entire scientific subfield and several companies pandering to this absurd fantasy. Here's a simplified diagram of caffeine metabolism: Caffeine is converted to a different stimulating chemical called paraxanthine by a liver enzyme called CYP1A2, over a half-life of ~5 hours. Then the same enzyme converts paraxanthine into other non-stimulating chemicals that don't matter, over a half-life of about three hours. Kman on Less Wrong has graphed the total effective concentration over time: Over the course of hours, the liver converts caffeine into paraxanthine. These are (by assumption) equally potent, so total effective concentration (the dashed red line) goes down slowly. (Why does it go down at all? Because of the simplification in the diagram above: only about 80% of caffeine is converted to paraxanthine; the rest is converted to other, less active metabolites.) By hour ten, paraxanthine predominates, the liver is mostly converting paraxanthine to other non-stimulating chemicals, and effective concentration continues to decrease. In this model, we see that the effective half-life of caffeine is close to ten hours1! What if we want it to be less? There are three levers we can pull: the enzyme, the metabolite, and the starting chemical. https://www.astralcodexten.com/p/the-quest-for-caffeine-you-can-have

[previously in series: 1, 2, 3, 4, 5, 6, 7, 8, 9] Paul Graham once said that every city sends a message. New York says you should make more money. Berkeley says you should live better. Boston says you should be smarter. People shouldn't decide on a permanent residence until they've lived in several cities and understand their differing psychological effects. San Francisco sends a message too. It speaks it in a cacophony of dissonant voices, some sounding like the hissing of snakes, others like the chittering of insects. "You should pierce the veil," it says, with a faint accent which you are not scholarly enough to recognize as ancient Sumerian. "You should rip through the flimsy screen that separates your world from the infinite, and witness what lies behind. Because you'd like what you saw there? Oh no, nothing like that. But aren't you curious? The thirst for knowledge that moved Eve, Faust, Pandora - don't you have it too?" There's also a second message from a second voice, one which sounds like a deranged carnival barker, constantly shouting "STONKS! STONKS! STONKS! STONKS!" Which of the two voices you hear depends on your personality, and maybe how many psychedelics you took in college. According to legend, Sam Altman hears both voices simultaneously all the time, like those Tibetan throat singers who can harmonize with themselves. But when the demonic babble becomes too much to tolerate, the San Franciscans drown it out with alcohol, loud music, and various forms of tedious socialization. Thus the famous Bay Area house parties, one of which you will be attending this very night. https://www.astralcodexten.com/p/the-foothills-of-bay-area-house-party

Old Scottish joke: A man at the bar is complaining: "You see that bridge there? I built it with my own hands! But do they call me 'MacGregor The Bridge-Builder'? No! And I raised five beautiful children! But do they call me 'MacGregor The Child-Raiser'? No! But, you f**k one sheep . . ." Has MacGregor been treated unfairly? https://www.astralcodexten.com/p/macgregor-the-bridge-builder

Last month, some of Silicon Valley's biggest companies signed an open letter supporting open-weights AI. Open weights AI is like open-source software, where the creator makes the raw code publicly available for free download. It's good insofar as it's the only way an AI can truly be the user's property, as opposed to something that companies like OpenAI or Anthropic temporarily let you use subject to their corporate guidelines and increasingly-nanny-state-like restrictions. If AI becomes the linchpin of the future, open weights AI feels like the sort of thing that could be the difference between being free yeomen vs. corporate serfs. It's bad insofar as it removes the possibility of gatekeeping and lets criminals commit crimes with it. Open weights AI could be used for hacking, child pornography, harassment, or terrorism (the weights can't commit the terrorism themselves, but they could give bomb-making or bioweapon-making advice). Since AIs have gotten very good - maybe superhuman - at hacking lately, the specter of a world where anyone can hack any site has gotten people grumbling that maybe open weights should be banned. It doesn't help that China produces the best open weights AI, making the idea seem foreign and almost unpatriotic. Proponents counter that "when AI is outlawed, only outlaws will have AI", arguing that bad people will get open weights AI regardless, and good people can use open weights AI to defend themselves. With the recent open letter, companies including Microsoft, NVIDIA, OpenAI, Intel, Amazon, Meta, Hugging Face, and over a hundred others have come out in favor of this position. Who's leading the other side? Nobody's admitted to it. Some parts of the Trump administration lean anti-open-weights on China hawk grounds, but have stopped short of explicitly asking for a full ban. Anthropic, the most notable omission on the pro-open-weights letter, made an ambiguous statement supporting "open-weights models that don't have dangerous capabilities" - but the industry expects open weights models to have dangerous hacking capabilities within a year, and AFAICT the letter didn't address that beyond inviting readers to draw the obvious conclusion. In the absence of a more obvious opponent, some open weights supporters suspect our conspiracy - the loose band of AI safety advocates, effective altruists, rationalists, and pause activists who worry about existential risk from superintelligence. This is a reasonable inference. By design, open weights AI is outside centralized control, and so impossible to permanently align against either human misuse (eg terrorism) or loss of control (eg AI turning against humans). Even if its creator trains it not to hack, anybody in the world can download the weights and retrain the AI to hack all day long. But in fact, most AI safety organizations have remained quietly neutral, and I don't know of any who make this a centerpiece of their activism1 (though I'm not 100% up-to-date on the whole landscape; if you know of one, tell me). A few have proposed policies that are contingently incompatible with open weights AI existing, but they all frame it as collateral damage rather than something they're excited about eliminating. I'm also neutral about open weights AI. I think it probably won't be long-term sustainable, but I'm happy to wait for this to become clear in the normal course of things rather than expend effort and political capital to ban it immediately. https://www.astralcodexten.com/p/open-questions-on-open-weights

Commenters convinced me I made a subtle mis-step in my framing of Psychology Research Is Mostly Fine. My framing emphasized that social priming studies had failed to replicate, but that many other subfields of psychology hadn't. This naturally led commenters to point to failed replications in other subfields. Although none of these were as bad as social priming, few or none were entirely problem-free. Instead of emphasizing the difference between social priming and other subfields, I should have emphasized the difference between settled science and novel research. Here are some of my favorite psychology findings: https://www.astralcodexten.com/p/the-beauty-of-settled-science

Superforecasting is the art/science/sport of predicting the future - for example, who will win elections, which countries will fight wars, when key technologies will be discovered. Over the past few years, it went from an obscure academic subfield to a multibillion dollar industry in the form of prediction markets. More recently, AI superforecasters have come close to the accuracy of top humans, and their performance is rising rapidly. In a year or two, we'll see one of the following patterns: Either humans have already come close to some fundamental limit on the predictability of world events - in which case AIs will plateau at or slightly above the human level - or the trend line will continue until AIs are far beyond top humans. By analogy to superintelligence, the natural term for the second situation would be "superforecasting"; since that's already in use, we can cringely call it "ultraforecasting". Daniel Reeves1 makes the case for scenario A here. He describes a study he coauthored in 2010, which found that, on a variety of questions related to sports games and movie box office receipts2, prediction markets only outperformed simple boring statistical models by 3-6%. Maybe those statistical models are close to the best that it's possible to do; the rest is what the mathematicians call aleatoric uncertainty - irreducible complexity downstream of chaotic systems that entirely resist modeling. He could be right. This post isn't meant to be a decisive refutation, but rather a description of why I'm still about 70-30 expecting Scenario B. https://www.astralcodexten.com/p/does-forecasting-have-room-at-the