Hilary Putnam is one of the most versatile philosophers of our time. He has written more than 20 books and more than 300 articles, on subjects ranging from mathematical logic to religion.
The work that is being rewarded with the 2011 Rolf Schock Prize in Logic and Philosophy belongs to the interface between philosophy of language, philosophy of science and metaphysics. In particular, it concerns the semantics for two sorts of linguistic expressions: theoretical terms in science, like ‘atom’ and ‘energy’, and everyday words for ‘natural kinds’, like ‘gold’ and ‘water’.
The starting point is Willard Van Orman Quine’s critique of the distinction between analytic and synthetic propositions. The former are said to be true by virtue of their meaning, while the truth of the latter also depends on the world. Thus, ‘all bachelors ride bicycles’ is synthetic, while ‘all bachelors are unmarried’ is analytic.
Unlike Quine, Putnam held fast to this example of analyticity: anyone who denies the proposition must be using one of the words to mean something other than we do. But for theoretical terms, no clear-cut distinction is possible. These terms are associated with clusters of natural laws. If we reject all statements of laws concerning energy, we have undoubtedly changed the meaning of the term ‘energy’; but for a change to take place it is unclear which, or how many, statements we must reject.
Accordingly, the meaning of theoretical terms can be preserved when a theory is modified. This revision of semantics makes, in turn, scientific realism possible: the new theory deals with the same phenomena as the old one.
Putnam subsequently combined these views with meaning externalism. The meaning of ‘natural kind’ terms, such as ‘water’, is determined by language users’ surroundings and not by the stereotypical characteristics they associate with the term, such as quenching thirst and flowing in rivers. On another planet outwardly just like ours, and perceived as such by its inhabitants, a substance other than H2O – XYZ, say – could have these characteristics instead. For speakers on this Twin Earth, ‘water’ would mean ‘XYZ’, while we should truthfully deny that there is any water on their planet. The conclusion is that ‘meanings just ain’t in the head’.
Hilary Whitehall Putnam was born in Chicago in 1926. After studies at the University of Pennsylvania and Harvard University, he received his PhD in 1951 from the University of California, Los Angeles, with Hans Reichenbach and Rudolf Carnap as his supervisors. In 1965, after a long residence at the Massachusetts Institute of Technology (MIT), he moved to Harvard where, in 1976, he was appointed as Walter Beverly Pearson Professor of Mathematical Logic. Today, he is Cogan University Professor Emeritus at Harvard University.
Putnam is a past President of the American Philosophical Association (Eastern Division), the Philosophy of Science Association and the Association for Symbolic Logic. He is a Fellow of the American Academy of Arts and Sciences, and a Corresponding Fellow of the British Academy (the UK’s national academy for the humanities and social sciences) and the French Académie de Sciences Morales et Politiques. He is married to Ruth Anna Putnam.