Gary Marcus

astonished that anyone knowledgeable could claim that neural nets are (obviously) an “abstraction of neural processing” when we don’t yet know how brains work. if you don’t know how Y works you can’t really speak with certainty about whether X is an abstraction of Y. Period.https://twitter.com/tyrell_turing/status/1200072223299657728 …

Gary, we know some things about how brains work, and we know that ANNs can capture these aspects. This is very well established. You are confusing two statements: (1) ANNs are an abstraction of neural processing (true). (2) ANNs are a good model of the brain (? - TBD).

If we don't know the answer to (2), how can we be sure about the answer to (1)?

We know enough of the basics of how individual neurons turn inputs to outputs to create an abstraction of that process. That is the solid statement that supports (1). (2) is dependent on how neurons interact & what further complexities are needed to capture all the brain does.

It may be fruitful & fashionable to say we dont understand anything about the brain & so cant model it. But that's simply not how modeling works. Its iterative and you go with your best guess until contradictory evidence provides you with a better one.