Reletter
Artwork for Astral Codex Ten

P(A|B) = [P(A)*P(B|A)]/P(B), all the rest is commentary.

Platform
Substack
PricingFreemiumPublishesDaily
Issues1427Founded6 years agoLast Issue5 days ago
Active

Read this Newsletter

astralcodexten.com
Artwork for Astral Codex Ten

Latest Issues

Introducing Plan A

A Is For America

It’s increasingly clear that nobody has a plan for if this AI thing turns out to be real. Some people have suggestions, but they’re all things like “regulate a little more” or “regulate a little less” or “react to things a...

5 days ago
68
17

Your Book Review: The Book Of Abraham

[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...

6 days ago
200
373

Open Thread 441

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...

8 days ago
43
653

The AI Superforecasters Are Here

The annual prediction market conference was earlier this month. This was the year prediction markets went from an obscure hobby to a multi-billion dollar industry; from semi-illegal to having the President’s son as an advisor. I can’t remem...

12 days ago
509
317

Hidden Open Thread 440.5

...

12 days ago
6
78
Paid

Key Facts

Contact Information
Newsletter Author
Number of Subscribers
Find out how many people subscribe to this newsletter.

Audience Metrics

Subscribers, engagement, traffic and sponsorship for Astral Codex Ten.

SubscribersEngagement93Monthly Web Visits
Accepts SponsorsEstimated Cost per Ad

SEO Reach

Where Astral Codex Ten ranks on Google, and how much search traffic it brings in.

Ranked Keywords5.7kMonthly Search TrafficTop Keywords

Chart Rankings

How this newsletter ranks in the official Substack charts.

#4
Substack
/Science(Free)
#3
Substack
/Science(Paid)

Authors

The writers behind this newsletter.

  • Scott Alexander
  • Sasha Putilin

    Psychotechnology: metarational approach. Psychedelics, meditation, neurotech, consciousness research. Plus occasional writing advice.

  • Frequently Asked Questions

    How can I access the email archive for Astral Codex Ten?

    You can find recent issues that have been published by Astral Codex Ten on Reletter by scrolling up to where it says Latest Issues. Tap on the link for any of the most recent emails or hit More Issues to see older ones.

    How many subscribers does Astral Codex Ten have?

    To see how many people subscribe to Astral Codex Ten, simply upgrade your Reletter account. We provide readership numbers and lots of other stats for this newsletter so you can decide if it's worth reaching out to.

    How can I advertise in Astral Codex Ten?

    Newsletter advertising can be extremely effective when it's done right. Before you pitch Astral Codex Ten as a potential sponsor or partner, make sure that you've done your research and checked its newsletter stats with Reletter.

    Then, personalize one of our winning pitching templates and send it to the right person using the contact info provided.

    How much does it cost to sponsor a publication like Astral Codex Ten?

    Newsletter ad rates (or CPM) vary depending on many factors, including industry, number of subscribers, open rate, ad placement and more.

    To find out how much an ad will cost, contact Astral Codex Ten using the contact information provided and ask for a copy of their media kit.

    How can I find newsletters related to Astral Codex Ten?

    Scroll up to where it says Related Newsletters to see other publications like Astral Codex Ten. You can also search our email newsletter directory to discover other newsletters that cover the topics you're interested in.

    How do I contact Astral Codex Ten?

    Reletter provides this newsletter's website URL above, where you will often find their contact information. We also provide links to associated social media accounts and pitching templates so you can reach out fast.