Some people say “the brain is a computer”. Other people say “well, the brain is not really a computer, because, like, what's the hardware versus the software?” I agree: “the brain is a computer” is kinda missing the mark. I prefer: “the brain is a machine that runs an algorithm”.

Here's a mechanical adder:

What's “hardware versus software” for a mechanical adder? The question is nonsense.

A mechanical adder is not “a computer”, analogous to a MacBook. Rather, it's a machine that runs an algorithm. (Namely, the binary addition algorithm.)

And the brain is likewise a machine that runs a (much more complicated) algorithm.

“A machine??”, you say. Yeah, you heard me. A machine. An extraordinarily complex machine, but a machine all the same. If you could zoom in enough to really see it, it would just be obvious! You should pause here to marvel at some molecular simulations of cell biology in action: DNA replication, more crazy DNA stuff, kinesin, and so on.

…And what else would you expect? We live in a universe that follows orderly laws of physics.[1] And the laws apply to our bodies and brains just like everything else. After all, scientists have been [...]

The original text contained 4 footnotes which were omitted from this narration.

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First published:
February 17th, 2026

Source:
https://www.lesswrong.com/posts/eKGjwRSQD3BLxmBcu/the-brain-is-a-machine-that-runs-an-algorithm

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Narrated by TYPE III AUDIO.

“The brain is a machine that runs an algorithm” by Steven Byrnes

LessWrong (30+ Karma)

“The brain is a machine that runs an algorithm” by Steven Byrnes