Introduction

This sequence is an attempt to sketch a unified framework for several interconnected questions: Where do Bayesian priors come from? What even are probabilities? How should we deal with infinite ethics? What's going on with anthropics? I hope to lay out both some of the existing answers and my own preferred synthesis.[1]

I understand that many people have already thought about these questions, and I have only read portions of the existing literature. I think most of what I will write here, even in the section about my preferred synthesis, is not novel. People whose writing I'm building on include Wei Dai, Paul Christiano, Joe Carlsmith, Scott Garrabrant and Richard Ngo. I've also listened to some people like Lukas Finnveden, Vivek Hebbar and Ryan Greenblatt talk about related topics, which was also influential on me.[2]

However, most of the prior work is scattered across many, often very confusingly written blog posts, and I can't easily tell where I first came across various ideas I'm exploring here. Therefore, I will not try to do a full exegesis of where each idea came from, and will instead present the arguments as a unified flow, with only occasional direct references to [...]

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Outline:

(00:10) Introduction

(01:48) What even are probabilities?

(03:39) Probabilities from priors

(05:13) Solomonoff induction

(06:32) Problems with Solomonoff induction

(13:11) Probabilities as betting odds

(15:22) Sleeping Beauty

(16:19) Sleeping Beauty taking bets

(17:19) The trouble with money-based definitions

(18:35) Betting on experiences

(20:53) Betting on terminal values

(22:04) Probabilities for the exotic and the mundane

(22:27) Probabilities in the mundane world

(23:36) Letting go of probabilities

(26:25) Conclusion

The original text contained 16 footnotes which were omitted from this narration.

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First published:
May 23rd, 2026

Source:
https://www.lesswrong.com/posts/o8PQcgpznf6GKszdA/probabilities-are-not-the-right-concept

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Narrated by TYPE III AUDIO.

“Probabilities are not the right concept” by David Matolcsi

LessWrong (30+ Karma)

“Probabilities are not the right concept” by David Matolcsi