It is an honor to have been selected among Murray's many friends and colleagues to speak to you this afternoon. No doubt I have been chosen because of the mathematical component present in high-energy theory today. Before concentrating on the interface of elementary particle physics and modern geometry, I'd like to record my own pleasure in knowing Murray this past decade. Perhaps it's just as well we didn't get acquainted earlier; I think he would have frightened me to death. You all are aware of Murray's great intellectual powers; but to me, equally amazing, is his enthusiasm for all creative endeavors, large and small. More than anyone, he firmly believes that the human mind and the human spirit can cure the ills of society. This birthday celebration expresses his personality in several ways. The diversity of topics reflects his many interests. And the theme stresses his positive view of the future.

Our charge was to pick some subject — mine is mathematics and physics — and discuss its present status and future prospects. Like twin stars, the two subjects have influenced each other greatly over the centuries, sometimes overlapping significantly, sometimes going their separate ways. In the fifties and sixties there was little contact — perhaps even some hostility. Physicists believed that too much mathematics hindered physical insight; some older ones still do. Mathematicians required more mathematical precision than physics deemed necessary and were developing abstract structures for their own sake.