This is my friend Susumu Hayashi. I knew him well in 1987, when I spent the summer in Japan. I haven't seen him in the twenty years since then! It was wonderful to see him again. Now he is a professor at the University of Kyoto, in "humanistic informatics", which is in the College of Arts and Letters rather than the College of Science. He has become interested in history, and stayed only two days in Bonn, then went to Göttingen to study the 700 handwritten letters of the mathematician David Hilbert that are kept in the library there. Of course, they are handwritten in German, which he has learned.