Seymour was born in New York City on October 15, 1921 to an immigrant family from Poland. He received a BA from Brooklyn College and a PhD from Purdue University, with both degrees in physics. He joined the physics faculty at Purdue in 1947. For most of us who knew Seymour as a preeminent biologist, it is difficult to appreciate completely his stature as a semiconductor physicist. Seymour solved one of the outstanding problems of his day: how to fabricate a germanium crystal rectifier capable of withstanding high back-voltages (>100V). This was the major contribution of Karl Lark-Horovitz's semiconductor group at Purdue and was crucial to the subsequent development of the transistor by William Shockley's group at Bell Labs. Seymour held five US patents related to the germanium crystal rectifier, two of these together with Lark-Horovitz.
Seymour was inspired to change directions from physics to biology, amazingly enough, by reading What is Life? by Erwin Schrödinger. Seymour learned molecular biology at the Cold Spring Harbor Laboratory Phage Course, then at Caltech with Max Delbrück and at the Pasteur Institute with Andre Lwoff, Francois Jacob and Jacques Monod. Returning to Purdue, he conducted his magnificent study on fine structure mapping of the rII gene in T4 bacteriophage. He identified thousands of rII mutations and mapped them linearly to hundreds of sites within the gene. In this powerful and elegant analysis, Seymour showed unequivocally and for the first time that there are no fundamental or conceptual barriers between classical genetics and the Watson-Crick model of the DNA molecule—there are only differences in scale and resolution.
