Jack was born July 20, 1926, in New York City. He died May 8, 2019, of natural causes in Eugene, Ore.
He graduated from Deerfield Academy. At Princeton he majored in psychology. He earned a master’s degree at Clark University, and then came back to Princeton and earned a Ph.D. in 1955. Jack was awarded a Bronze Star as an Army staff sergeant in Europe and in combat.
As a full professor at the University of Oregon and with visiting appointments at other universities, his lifelong career was as a teacher, researcher, author, and consultant on organizational development and behavior, management, and entrepreneurship. A fellow of the American Psychological Society and with a term as president of the American Academy of Management, he was active in and received numerous awards from these and other academic and professional organizations.
Jack had three marriages. The longest, for 46 years, was to Barbara, who survives him. Together they parented five children and stepchildren and 12 grandchildren. They all survive him.