This is news to me. I had been steeped in a different lore. I have read the original article (or perhaps it was an excerpt?). I don't recall this reference. I

This is news to me. I had been steeped in a different lore. I have read the original article (or perhaps it was an excerpt?). I don't recall this reference. I see from the wikipedia article you linked to, that they did know about the multiple layers. I thought it was suspicious that they had somehow missed it since it is so simple (at least to us now), and these guys are so very smart. I wonder if they also knew (or realized, rather), that a single layer neuron with a non-monotonic function could have also "solved" XOR.