By the way, the story about the two pictures of a field, with and without army tanks in the picture, comes from me. I attended a meeting in Los Angeles, about half a century ago where someone gave a paper showing how a random net could be trained to detect the tanks in the picture. I was in the audience. At the end of the talk I stood up and made the comment that it was obvious that the picture with the tanks was made on a sunny day while the other picture (of the same field without the tanks) was made on a cloudy day. I suggested that the “neural net” had merely trained itself to recognize the difference between a bright picture and a dim picture.
Ed Fredkin has since sent me a personal email: