Churchland is a leading proponent of so-called eliminative materialism in the philosophy of mind. In contrast to a reductive materialism which claims that mental processes are in some way identical with physical (e.g. brain) processes, eliminative materialism claims that mental processes as traditionally conceived do not exist. Churchland defends this thesis by arguing that the network of concepts and principles which common sense relies on in explaining mental processes and behaviour is a scientific theory, albeit of a primitive kind. But this network (sometimes called folk psychology) is in fact a poor scientific theory when judged by the normal scientific requirements of predictive and explanatory success. In place of folk psychology Churchland proposes a theory (or set of interlocking theories) based on a fusion of neuroscience and artificial intelligence. This naturally requires a fairly detailed consideration of the findings of these disciplines, and Paul Churchland's work here is smoothly complemented by that of his wife Patricia, whose work tends to have a greater empirical emphasis than his. Critics have objected to a number of aspects of this general programme. Some have argued that folk psychology is not a scientific theory at all, or, that if it is one, it is not a bad one (Wilkes, Sterelny, McGinn). Other critics have objected that Churchland's version of materialism is unble to provide any convincing account either of the intentional states (believing that, desiring that, etc.) or of mental states with a qualitative 'feel' to them.
Polish, b: 13 June 1884, Zakopane, Poland, d: 20 August 1944, Moscow. Cat: Logician; analytical philosopher; aesthetician; painter. Educ: Jagiellonian University and Academy of Fine Arts, Cracow. Infls: S. Pawlicki, W. Heinrich, H. Poincaré and B. Russell. Appts: 1930-9, Professor of Logic, John Casimir University, Lvov.
In logic Chwistek proposed a certain simplification of the Russellian theory of types; he also elaborated his own version of the pure theory of types. He made a suggestion of bracketless logical notation (next developed by J.Łukasiewicz). He introduced the precision notion of semantics. Using the method of explication by formalization (the so-called constructive method) he created an axiomatic system of elementary semantics (the notion of containment of one expression in another being primitive). He also made an exact rendering of rules of definition. In the field of the foundations of mathematics he was the creator of the so-called rational metamathematics. In semiotics he described the peculiarities of natural languages: their indefiniteness, ambiguity and self-contradiction.
His epistemology was founded on broad empiricism and realism. In ontology, his conception of plurality of realities (including natural, physical, phenomenalistic and visional) influ