Free will is like temperature: a useful tool for analyzing the behavior of certain systems which are too big and complicated to model in exact detail.

If you know the positions and velocities of every atom in a box of gas, then with enough work you can predict its future to arbitrary precision; does the gas "have a temperature"? Irrelevant! Technically yes, I guess, but it's sort of an epiphenomenon, screened off from reality by your exact knowledge of the initial conditions and your willingness to throw processor cycles at your simulation. But if you're less-than-perfectly omniscient, it might be more convenient to consider the box as having a "temperature" and model it more abstractly.

Substitute "person+environment"/"free will" for "box of gas"/"temperature" and that's all still true.

Maybe your box of gas is supercooled; if you know the initial conditions exactly, you can predict exactly when and where the first large droplet will nucleate, but if your vision of the box is even a little bit fuzzy, you'll instead need to use your understanding of "temperature" to build a probability distribution over when it will condense / whether it will be on a wall or in the gas's [...]

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First published:
August 12th, 2026

Source:
https://www.lesswrong.com/posts/JSteskb3Lgp9Be69o/free-will-is-like-temperature

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“Free will is like temperature” by Optimization Process

LessWrong (30+ Karma)

“Free will is like temperature” by Optimization Process