Audio note: this article contains 55 uses of latex notation, so the narration may be difficult to follow. There's a link to the original text in the episode description.

Summary:

This post outlines how a view we call subjective naturalism[1] poses challenges to classical Savage-style decision theory. Subjective naturalism requires (i) richness (the ability to represent all propositions the agent can entertain, including self-referential ones) and (ii) austerity (excluding events the agent deems impossible). It is one way of making precise certain requirements of embedded agency. We then present the Jeffrey–Bolker (JB) framework, which better accommodates an agent's self-model and avoids forcing her to consider things she takes to be impossible.[2]

1. Subjective Naturalism: Richness & Austerity

A naturalistic perspective treats an agent as part of the physical world—just another system subject to the same laws. Among other constraints, we think this means:

Richness: The model [...]

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Outline:

(01:00) 1. Subjective Naturalism: Richness and Austerity

(02:06) 1.1. Framework vs. Action-Guiding Rule

(04:15) 2. Savage's Framework

(06:22) 3. The Jeffrey-Bolker Framework

(06:37) 3.1. Basic Setup

(07:41) 3.2. A Key Axiom (Informally)

(08:32) 3.3. Richness in Jeffrey-Bolker

(09:03) 3.4. Austerity in Jeffrey-Bolker

(10:18) 4. Comparison and Key Advantages

(11:19) 5. Concluding Remarks

The original text contained 15 footnotes which were omitted from this narration.

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First published:
February 4th, 2025

Source:
https://www.lesswrong.com/posts/FL8RunWvyS5L8uJEw/subjective-naturalism-in-decision-theory-savage-vs-jeffrey

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Narrated by TYPE III AUDIO.

“Subjective Naturalism in Decision Theory: Savage vs. Jeffrey–Bolker” by Daniel Herrmann, Aydin Mohseni, ben_levinstein

LessWrong (30+ Karma)