The most influential American philosopher of the latter half of the 20th century, Quine was born in Akron, Ohio, of partly Dutch and partly Manx descent. After Oberlin College he did graduate work at Harvard, gaining his doctorate in 1932 for work developing and refining the system of logic of Russell and Whitehead’s Principia Mathematica. A Fellowship and a year abroad brought Quine into contact with the Vienna circle (see logical positivism), with Carnap in Prague, and with Tarski in Warsaw. Returning to Harvard, Quine eventually became Faculty Instructor in 1936 and associate professor in 1941. After a wartime period in naval intelligence, Quine became full professor at Harvard in 1948, punctuating the rest of his career with extensive foreign lecturing and travel.

Quine’s early work was on mathematical logic, and issued in A System of Logistic (1934), Mathematical Logic (1940), and Methods of Logic (1950). It was with the collection of papers From a Logical Point of View (1953) that his philosophical importance became widely recognized. His celebrated attack on the analytic/synthetic distinction heralded a major shift away from the views of language descended from logical positivism, and a new appreciation of the difficulty of providing a sound empirical basis for theses concerning convention, meaning, and synonymy. Quine’s work dominated subsequent interest in these problems.

His reputation was cemented by Word and Object (1960), in which the indeterminacy of radical translation first takes centre stage. In this and many subsequent writings Quine took a bleak view of the nature of the language with which we ascribe thoughts and beliefs to ourselves and others. These ‘intentional idioms’ resist smooth incorporation into the scientific world view, and Quine responded with scepticism towards them, not quite endorsing eliminativism, but regarding them as second-rate idioms, unsuitable for describing strict and literal facts. For similar reasons he has consistently expressed suspicion of the logical and philosophical propriety of appeal to logical possibilities and possible worlds. The languages that are properly behaved and suitable for literal and true description of the world are those of mathematics and science. The entities to which our best theories refer must be taken with full seriousness in our ontologies: although an empiricist, Quine thus supposed that the abstract objects of set theory are required by science, and therefore exist. In the theory of knowledge Quine is associated with a holistic view of verification (see also Duhem thesis), conceiving of a body of knowledge in terms of a web touching experience at the periphery, but with each point connected by a network of relations to other points. Quine was also known for the view that epistemology should be naturalized, or conducted in a scientific spirit, with the object of investigation being the relationship, in human beings, between the inputs of experience and the outputs of belief. Although Quine’s approaches to the major problems of philosophy have been attacked as betraying undue scientism and sometimes behaviourism, the clarity of his vision and the scope of his writing made him the major focus of Anglo-American work of the second half of the 20th century in logic, semantics, and epistemology. As well as the works cited, his writings include The Ways of Paradox and Other Essays (1966), Ontological Relativity and Other Essays (1969), Philosophy of Logic (1970), The Roots of Reference (1974), and The Time of My Life: An Autobiography (1985).