Quine, Willard Van Orman (1908–2000)
Authors: Orenstein Alex 
Published: September 2018

Quine is the foremost representative of naturalism in the second half of the twentieth century. His naturalism consists of an insistence upon a close connection or alliance between philosophical views and those of the natural sciences. Philosophy so construed is an activity within nature wherein nature examines itself. This contrasts with views which distinguish philosophy from science and place philosophy in a special transcendent position for gaining special knowledge. The methods of science are empirical; so Quine, who operates within a scientific perspective, is an empiricist, but with a difference. Traditional empiricism, as in Locke, Berkeley, Hume and some twentieth-century forms, takes impressions, ideas or sense-data as the basic units of thought. Quine’s empiricism, by contrast, takes account of the theoretical as well as the observational facets of science. The unit of empirical significance is not simple impressions (ideas) or even isolated individual observation sentences, but systems of beliefs. The broad theoretical constraints for choice between theories, such as explanatory power, parsimony, precision and so on, are foremost in this empiricism. He is a fallibilist, since he holds that each individual belief in a system is in principle revisable. Quine proposes a new conception of observation sentences, a naturalized account of our knowledge of the external world, including a rejection of a priori knowledge, and he extends the same empiricist and fallibilist account to our knowledge of logic and mathematics.
Quine confines logic to first-order logic and clearly demarcates it from set theory and mathematics. These are all empirical subjects when empiricism is understood in its Quinian form. They are internal to our system of beliefs that make up the natural sciences. The language of first-order logic serves as a canonical notation in which to express our ontological commitments. The slogan ‘To be is to be the value of a variable’ ([1953] 1961: 15) encapsulates this project. Deciding which ontology to accept is also carried out within the naturalistic constraints of empirical science – our ontological commitments should be to those objects to which the best scientific theories commit us. On this basis Quine’s own commitments are to physical objects and sets. Quine is a physicalist and a Platonist, since the best sciences require physical objects and the mathematics involved in the sciences requires abstract objects, namely, sets.
The theory of reference (which includes notions such as reference, truth and logical truth) is sharply demarcated from the theory of meaning (which includes notions such as meaning, synonymy, the analytic–synthetic distinction and necessity). Quine is the leading critic of notions from the theory of meaning, arguing that attempts to make the distinction between merely linguistic (analytic) truths and more substantive (synthetic) truths has failed. They do not meet the standards of precision which scientific and philosophical theories adhere to and which are adhered to in the theory of reference. He explores the limits of an empirical theory of language and offers a thesis of the indeterminacy of translation as further criticism of the theory of meaning.