1909-

American mathematician. After graduating from Yale in 1930, MacLane traveled to Germany to enroll at the prestigious Göttingen University—the center of European mathematics at that time. However, when the Nazis came to power in the 1930s, he quickly completed his doctorate with his dissertation, "Abbreviated Proofs in the Logical Calculus," and immediately returned to America. In 1947 he was appointed professor of mathematics at Chicago University and, five years later, was given the chair of that department, which he held until his retirement.