I did actually read his 2004 book (after writing this post), and as far as I can tell, he doesn’t really seem to have changed his mind about anything, except details like “What exactly is the function of 5th-layer cortical neurons?” etc.
In particular, his 2004 book gave the impression that artificial neural nets would not appreciably improve except by becoming more brain-like. I think most neutral observers would say that we’ve had 15 years of astounding progress while stealing hardly any ideas from the brain, so maybe understanding the brain isn’t required. Well, he doesn’t seem to accept that argument. He still thinks the path forward is brain-inspired. I guess his argument would be that today’s artifical NN’s are neat but they don’t have the kind of intelligence that counts, i.e. the type of understanding and world-model creation that the neocortex does, and that they won’t get that kind of intelligence except by stealing ideas from the neocortex. Something like that...
I did actually read his 2004 book (after writing this post), and as far as I can tell, he doesn’t really seem to have changed his mind about anything, except details like “What exactly is the function of 5th-layer cortical neurons?” etc.
In particular, his 2004 book gave the impression that artificial neural nets would not appreciably improve except by becoming more brain-like. I think most neutral observers would say that we’ve had 15 years of astounding progress while stealing hardly any ideas from the brain, so maybe understanding the brain isn’t required. Well, he doesn’t seem to accept that argument. He still thinks the path forward is brain-inspired. I guess his argument would be that today’s artifical NN’s are neat but they don’t have the kind of intelligence that counts, i.e. the type of understanding and world-model creation that the neocortex does, and that they won’t get that kind of intelligence except by stealing ideas from the neocortex. Something like that...