I don't know how many people know that Heinz is a magician and a member of the Magic Circle, but he is. He demonstrated some his skills in this field in 1960, when he and Gordon, Ross Ashby, Warren McCulloch, and other cyberneticians and their wives were very generously entertained by the Barth Foundation in Switzerland. In the course of this visit, we spent a night at the circus. Imagine our feelings when Heinz suddenly disappeared and then reappeared in the circus ring, he was wearing a selection of hats and riding a monocycle. He circled the ring with great aplomb, taking off his various hats with enormous style. What a star! He said he did to make up for his lack of beard, as the lady organising the event had expected all her professors to be bearded like the 'pard.
A small incident in a long and fruitful life, but one that gave his friends a great deal of pleasure, and very typical of Heinz.