Mathematician and idealist philosopher, born in Ramsgate, Kent. He studied at Cambridge, where he was senior lecturer in mathematics until 1910. He then taught at London Imperial College (1914-24), and was then professor of philosophy at Harvard (1924-37). He collaborated with his former pupil, Bertrand Russell, in writing the Prinicipia Mathematica (1910-13). Other more popular works include Adventures of Ideas (1933) and Modes of Thought (1938).

See also Giuseppe Peano.