The Globe and Mail 27 April 2005 Obituaries Saunders Mac Lane, 95 CHICAGO MATHEMATICIAN INTRODUCED 'FUNCTORS' Associated Press 77 words S7 Chicago -- Saunders MacLane, a leading American mathematician and a professor at the University of Chicago for nearly four decades, died April 14 in San Francisco after a long illness. He was 95. In a landmark paper he co-authored with Samuel Eilenberg in 1945, Prof. Mac Lane developed new ways of thinking about mathematics introducing what are known as "categories," "functors" and "natural transformations." 27-Apr-2005 13:04:19 -0300,3561;000000000000-0000001a