born Sept. 4, 1927, Boston, Mass., U.S.
U.S. computer scientist.
He received his Ph.D. from Princeton University. A pioneer in the field of LISP in 1958. He also developed ideas about the processing characteristics of trees (as used in computing), as distinct from nets. He is a recipient of the Turing Award (1971), the Kyoto Prize (1988), and the National Medal of Science (1990).