Walter Boughton Pitkin (born February 6, 1878 in Ypsilanti, Michigan; died January 25, 1953 in Palo Alto, California) was an American lecturer in philosophy and psychology at Columbia University (1905–09), and professor in the Columbia University School of Journalism (1912–43). He has written some self-help books like Life Begins at Forty (New York, Whittlesey house, McGraw-Hill, 1932) and The Psychology of Happiness. His A Short Introduction to the History of Human Stupidity was translated into fifteen languages. Pitkin was a member of the New Realism school in philosophy, writing on its relation to biology.
Pitkin was father (by Mary Gray Pitkin) to five sons: Richard G., John G., David B., Robert B., and Walter B Pitkin Jr. He later married Katherine B. Johnson.