Why does a water bottle seem like a natural chunk of physical stuff to think of as “A Thing”, while the left half of the water bottle seems like a less natural chunk of physical stuff to think of as “A Thing”? More abstractly: why do real-world agents favor some ontologies over others?

At various stages of rigor, an answer to that question looks like a story, an argument, or a mathematical proof. Regardless of the form, I’ll call such an answer an ontological foundation.

Broadly speaking, the ontological foundations I know of fall into three main clusters.

Translatability Guarantees

Suppose an agent wants to structure its world model around internal representations which can translate well into other world models. An agent might want translatable representations for two main reasons:

Language: in order for language to work at all, most words need to point to internal representations which approximately “match” (in some sense) across the two agents communicating.
Correspondence Principle: it's useful for an agent to structure its world model and goals around representations which will continue to “work” even as the agent learns more and its world model evolves.

Guarantees of translatability are the type of ontological [...]

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Outline:

(00:45) Translatability Guarantees

(02:24) Environment Structure

(03:41) Mind Structure

(04:38) All Of The Above?

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First published:
November 10th, 2025

Source:
https://www.lesswrong.com/posts/JdwSvrJhHX8XT46Mc/three-kinds-of-ontological-foundations

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Narrated by TYPE III AUDIO.

“Three Kinds Of Ontological Foundations” by johnswentworth

LessWrong (30+ Karma)