Maurice Campbell Cornforth (28 October 1909 – 31 December 1980) was a British Marxist philosopher. When he began his career in philosophy in the early 1930s, he was a follower of Wittgenstein, writing in the then current style of analytic philosophy. He later became a leading ideologist of the Communist Party of Great Britain.
He is noted for his attack on the aesthetic theories of Christopher Caudwell, and for his later partial engagement with the linguistic philosophy of Oxford origin of the 1940s and 1960s. He also wrote a defence of Marxism against Karl Popper, whose thought he heavily criticized.
His In Defense of Philosophy attacks, in their relationship to science, empiricist philosophies of many kinds, such as those of Rudolf Carnap (linguistic analysis) and William James (pragmatism), on the "materialist" grounds that they divorce science and scientific investigation from the search for truer understanding of the really existing universe. In this book there is a combination of Marxism with deep insights into the interrelations of the various sciences and the philosophical conundrums produced by the empiricist attempt to reduce science to the collection and correlation of data. Both the insights are based on the theory of the primacy of physical work and tools (thus, "materialism") in the development of specifically human traits such as language, abstract thought, and social organization, and the essential role of the external world in the increasingly complex development of forms of life. These latter ideas are remarkably consistent with the most current evolutionary thinking in biology and anthropology.