Rudolf Carnap

German-American philosopher active in Europe before 1935 and in the United States thereafter. He was a major member of the Vienna Circle and an advocate of logical positivism. He is considered "one of the giants among twentieth-century philosophers."

He studied physics and math from 1910 to 1914. After serving in the military, he attained his doctorate in 1921 with a thesis on different concepts of space that foreshadowed his later style and interests. His books include "The Logical Structure of the World," 1928, "The Logical Syntax of Language," 1934, and "Meaning and Necessity," 1947. Carnap became a naturalized U.S. citizen in 1941. He died on 14 September 1970, aged 79, in Santa Monica, California.