Astral Codex Ten
Scott Alexander, SkylerP(A|B) = [P(A)*P(B|A)]/P(B), all the rest is commentary.
| Platform |  | Pricing | Freemium | Publishes | Daily |
|---|---|---|---|---|---|
| Issues | 1497 | Founded | 6 years ago | Last Issue | 3 days ago |
| Active | |||||
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astralcodexten.comLatest Issues
Why Global Trepanation?
A friend asked me to investigate the following mystery: why do 5-10% of skulls from 10,000 BC to 3,000 BC, all over the world, have holes in them? Why do bone growth patterns indicate that most skull-hole-havers survived years after their h...
Against Against Handover
The latest bugbear is “AI successionism”, the belief that AIs should succeed humans as rulers of Earth. But some critiques fail to distinguish between two different ideas.
True successionism says that AIs should take over, killing humans o...
Open Thread 456
This is the weekly visible open thread. Post about anything you want, ask random questions, whatever. ACX has an unofficial subreddit, Discord, and bulletin board, and in-person meetups around the world. Most content is free, some is subscr...
Your Book Review: Storm Of Steel
[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...
Meetups Everywhere 2026: Times & Places
By Meetups Czar Skyler:
There are two laws of the ACX Meetup Czar. First, that there are a lot of ACX meetup groups. Second, that there are not enough ACX meetup groups.
Twice a year, Scott advertises upcoming meetups and makes a bigger...
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Authors
The writers behind this newsletter.
I'm Skyler, AKA Screwtape. Starting early in 2023, I'm the ACX Meetups Czar. I also do the NYC Rationalist Megameetup, the Animorphs: The Reckoning podfic, and lots of RPGs.
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