Malcolm Thorndike Nicholson in Prospect:
Within the world of academic philosophy, Putnam is famous (perhaps notorious is the word) for his habit of changing his mind. His entry in the joke Philosophical Lexicon runs:
“Hilary: A very brief but significant period in the intellectual career of a distinguished philosopher. “Oh, that’s what I thought three or four hilaries ago.”
His longtime admirer Sidney Morgenbesser once quipped of Putman: “He’s a quantum philosopher. I can’t understand him and his position at the same time.”
This intellectual mutability extends to his politics and personal life. Born in 1926 to an intellectually gifted, middle-class Jewish family in Chicago, Putnam was raised an atheist and progressive. In the 1960s Putman was a vocal defender of the Civil Rights Movement, a critic of the American involvement in Vietnam, and a member of the communist Progressive Labor Party. By 1976 Putnam, after grappling with the human rights abuses by communists, left the PLP and gave up his support for Maoism. Both Putnam and his wife, the philosopher Ruth-Anna Putnam, returned to Judaism after decades of atheism. Putnam was 68 when he had his Bar Mitzvah.
Changing your mind in any situation, much less academic philosophy, is seen as a sort of weakness. It takes a very secure ego to end a debate with “well I think I may have been wrong.” Putnam’s shifts in position demonstrate not just his intellectual confidence, but also the virtue of seeing the bigger picture. Putnam is able to step back for a moment and see a particular position, say functionalism in philosophy of mind, and notice that it doesn’t quite fit in with a greater commitment in metaphysics and philosophy of language.
In Philosophy in an Age of Science Putnam wants us to take a step back and consider the relationship between two deeply entrenched ways of understanding the world. One, the scientific position, attempts to explain things in mind-independent and law-like terms. This is often called the descriptive or “is” position. The other, the moral position, attempts to explain things in mind-dependent and value-laced terms. This is often called the normative or “ought” position.