proving, computer-aided design, model checking in systems biology, and so forth. Jack seemed to have returned over and over to the core essence of mathematics to look for simple and elegant solutions to a diverse set of applications.
In an essay on computer science, Jack pithily described what he considered to be this essence of mathematics. “To find the simple in the complex, the finite in the infinite,” Jack wrote, “that is not a bad description of the aim and essence of mathematics.” To find the simple in the complex is not a bad description of what Jack’s work continues to represent to his friends, colleagues, mentees, advisees, and students.
Jack’s personal interests were wide and varied and included etymology, world music, music composition using software, middle school mathematics curriculum development, 3-D vision, Paleolithic stone implements, visual illusions, knots, extensive reading and cooking. In his final year Jack became interested in the basics of geometric lens optics and delved into the subject deeply enough to have started a paper on the topic. Up until one month prior to his death he was still working on transfer methods using wood, marble and clay.
Besides his wife, Diana, survivors include his daughters, Abby Schwartz of Manhattan and Rachel Fainman of Winnipeg, Manitoba; two grandchildren, Adam and Adrienne Fainman of Winnipeg, Manitoba; and a sister, Judith Dunford, the widow of the literary critic Alfred Kazin.