Harvard Square—a loosely defined ten- to twelve-block area in the heart of Cambridge, Massachusetts, articulated by a maze of streets and characterized by the interpenetration of university and commercial interests—is full of life, crowded, stimulating, and noisy. Cars, taxis, buses, and a subway station service a constant and remarkably diverse flow of humanity. Students and professors represent only a small fraction of this international, polyglot urban population. Musicians, jugglers, glass harmonica players, and political activists vie for prime sidewalk locations, while youth in punk attire add color. And yet, immediately adjacent to the square, there are a few quiet, narrow, one-way streets lined with buildings from the nineteenth and even eighteenth centuries. For four decades Leon Kirchner made his home in one of these idyllic havens, at 8 Hilliard Street.

On August 12, 2003, I visited him there to continue the series of interviews that I had been conducting over the previous two years. His son, Paul, greeted me at the door and led me to the living room, where I was to wait, as I had done so often in the past, for the master to come down from his room on the second floor of the elegant, but rundown, Victorian structure, just blocks from the very center of the square. Paul summoned his father, who appeared within a few minutes. Even at eighty-four, Kirchner’s erect and imposing six-foot-oneinch frame had lost very little altitude to the ravages of time. Admittedly, his movements were slow, and he carefully settled into the low sofa across from me, his lanky legs stretched out, almost bridging the distance between us. He had just returned two days earlier from a trip to New York City, and—totally without preamble—he launched immediately into a report.

“We were at a cocktail party and met scientists from Cold Spring Harbor where McClintock, the Nobel Prize winner, had worked. They invited us out to their laboratory. But I was nervous about going, because Watson was going to be there. After what had happened years ago, I didn’t want to encounter him.” Assuming that I knew something about Cold Spring Harbor, McClintock, and Watson (which I did not) he apparently was not going to offer further explanation.