Purva Mimamsa. SEE MIMAMSA. Putnam, Hilary (b.1926), American philosopher who has made significant contributions to the philosophies of language, science, and mind, and to mathematical logic and metaphysics. He completed his Ph.D. in 1951 at the University of California (Los Angeles) and has taught at Northwestern, Princeton, MIT, and Harvard. In the late 1950s he contributed (with Martin Davis and Julia Robinson) to a proof of the unsolvability of Hilbert’s tenth problem (completed in 1970 by Yuri Matiyasevich). Rejecting both Platonism and conventionalism in mathematics, he explored the concepts of mathematical truth and logical necessity on the assumption that logic is not entirely immune from empirical revision – e.g., quantum mechanics may require a rejection of classical logic. In the 1950s and 1960s he advanced functionalism, an original theory of mind in which human beings are conceived as Turing machines (computers) and mental states are functional (or computational) states. While this theory is presupposed by much contemporary research in cognitive science, Putnam himself (in Representation and Reality, 1988) abandoned the view, arguing that genuine intentionality cannot be reduced to computational states because the content of beliefs is (a) determined by facts external to the individual and (b) individuatable only by interpreting our belief system as a whole (meaning holism).
Putnam’s criticism of functionalism relies on the ‘new theory of reference’ – sometimes called the ‘causal’ or ‘direct’ theory – that he and Kripke (working independently) developed during the late 1960s and early 1970s and that is today embraced by many philosophers and scientists. In ‘The Meaning of ‘Meaning’ ‘ (1975) Putnam claims that the reference of natural kind terms like ‘water’ is determined by facts about the world – the microphysical structure of water (H2O) and the linguistic practices of speakers – and not by the internal mental states of speakers.
Early in his career, Putnam championed scientific realism, rejecting conventionalism and arguing that without a realist commitment to theoretical entities (e.g., electrons) the success of science would be a ‘miracle.’ In 1976 he famously abandoned metaphysical realism in favor of ‘internal realism,’ which gives up commitment to mind-independent objects and relativizes ontology to conceptual schemes. In a series of model-theoretic arguments, Putnam challenged the metaphysical realist assumption that an epistemically ideal theory might be false, claiming that it requires an implausibly ‘magical’ theory of reference. To the same end, he sought to demonstrate that we are not ‘brains in a vat’ and that radical skepticism is incoherent (Reason, Truth and History, 1981). More recently, he has emphasized conceptual relativity in his attack on metaphysical realism’s commitment to ‘one true theory’ and, in his Dewey Lectures (1994), has defended direct perceptual realism, showing his allegiance to everyday ‘realism.’
There is growing appreciation of the underlying unity in Putnam’s work that helps correct his reputation for ‘changing his mind.’ He has consistently sought to do justice both to the ‘real world’ of common sense and science and to distinctly human ways of representing that world. In the 1990s his energies were increasingly directed to our ‘moral image of the world.’ Leading a revival of American pragmatism, he has attacked the fact–value dichotomy, articulating a moral view that resists both relativism and authoritarianism. Putnam’s influence now extends beyond philosophers and scientists, to literary theorists, cognitive linguists, and theologians. See also CAUSAL THEORY OF PROPER NAMES , FUNCTIONALISM , MEANING , PHILOSO – PHY OF LANGUAGE , PHILOSOPHY OF SCIENC. D.L.A.
