J.S.: You started as a physicist but arrived here a combinatorialist, is that right? D.J.K.: Yes, that is correct. How did that happen? Well, you know, when I grew up I never actually got the impression that it was possible to make a living as a mathematician. My older brother went into physics, and I was a few years behind him, so it was the natural thing to me to study physics. I loved mathematics in college, but I went to graduate school at Harvard and got my degree in physics in ’58. Then I had an NSF post-doc, and I went to the University of Copenhagen’s Niels Bohr Institute for a year, and then the second year I spent at Harvard. And then I got an assistant professorship at Brandeis.