F.H.C. Crick

"Few people realize what an astonishing achievement it is to be able to see at all. The main contribution of the new field of artificial intelligence has been not so much to solve these problems of information handling as to show what tremendously difficult problems they are. When one reflects on the number of computations that must have to be carried out before one can recognize even such an everyday simple scene as another person crossing the street, one is left with a feeling of amazement that such an extraordinary series of detailed operations can be accomplished so effortlessly in such a short space of time."

from "Thinking about the Brain," in The Brain, 1979, p. 130