This is too long ago for me to know what actually happened. Both Rosenblatt as well as Minsky and Papert knew that networks could perfectly learn the XOR functi

This is too long ago for me to know what actually happened. Both Rosenblatt as well as Minsky and Papert knew that networks could perfectly learn the XOR function. See https://en.wikipedia.org/wiki/Perceptrons_(book) https://en.wikipedia.org/wiki/Perceptrons_(book) and also stated in this article. I knew there was a fight between Minsky and Grossberg at that time. Perhaps there have been other reasons that are not so well known that led to an AI winter. Have these winters ever be quantified though? For the article, you can find it in here: http://msrvideo.vo.msecnd.net/rmcvideos/258318/dl/258318.pdf http://msrvideo.vo.msecnd.net/rmcvideos/258318/dl/258318.pdf