> Isn't "the amalgamation of many smaller problems working together and building on top of each other" a fair description of the theorical Unix system?
Yes. Note the success of Unix and the ability to scale, do work and provide an environment to be productive in.
> Aren't your criteria for "intelligence" human-centric, implying that there is no other form of "intelligence"?
Your use of 'human-centric' is odd. I would have thought the traditional 'human-centric' theory of the mind is something monolithic and indivisible. Suggesting that it's many small processes communicating with each other is basically taken straight out of nature, from ants, schools of fish, birds flocking, etc.
Whether there are other forms of intelligence or no, it's clear that incremental progress in individual processes that can then be composed together is a productive way to traverse the energy landscape. This is why (imo) we see so many symbiotic relationships from cells on up to higher level animals.
> Aren't your criteria of the "black box" type, given that AFAIK no human can really completely explain how he recognizes faces/does NLP/walks/...?
I'm not quite sure what your point is here. If you're critiquing me about neural networks being black boxes and not giving us real insight into the underlying system, that's fair and the reason why I said I didn't like the black box aspect of neural networks. I will say that if there is a black box model that can be easily manipulated, this will probably lead to deeper models much quicker.
If you're saying that human cognition is not describable by any human and, I guess, implying that it's indescribable, I would point out that one doesn't follow from the other. Not having a good model right now doesn't imply we won't understand it at some future date and, in my opinion, this is precisely what's happening. Having no human be able to describe the underlying computation (of face recognition, nlp, walking etc.) doesn't mean it's indescribable, it means it's not describable by anyone right now.
At one point we didn't know how birds flew. We still might not know, to your satisfaction, but we have a basic understanding of how to make things fly, both in practical and theoretical terms. Planes fly and we understand how even though they don't flap their wings. I have no doubt we'll figure out how to do complex human-level computation even if we don't have a deep model of the specifics of human thought.