alt Hacker NewsWe don't know all the details about how the brain computes, you are right.
But we do have a hypothesis: that it is done by a large number of simple units with very high connectivity and in deep layers. This is what neural networks model.
Personally I was skeptical of this model of the brain, but they have achieved remarkable success in practice, as well as Nobel prizes. The neural networks people may have been onto something all along (I say that grudgingly).
But the models learn in a very different way than humans, they're certainly vastly more sample inefficient. I'm not saying it isn't impressive or that it isn't necessarily a kind of intelligence, I'm just sceptical as to how much it really tells us about the brain.