Charles Sanders Peirce

An American philosopher, logician and scientist, the founder of pragmatism. He worked for thirty years with the United States Coast and Geodetic Survey and held an academic post only briefly, at Johns Hopkins, but wrote prolifically on logic, the theory of signs and the method of science. His essays “The Fixation of Belief” and “How to Make Our Ideas Clear” (1877–78) first set out the pragmatic maxim.