Putnam, Hilary - Wittgenstein and Realism

08/10/2012

Philosophy in an Age of Science, Ch 22 Harvard University Press, 2012

Author starts with Wittgenstein's line from the Tractatus proposing an equivalence between solipsism and "pure realism". In figuring out what notion of solipsism Wittgenstein had in mind, author turns to an interpretation offered by Brian McGuinness, whereby Wittgenstein was trying to both contradict and reconcile Schopenhauer's 'famous dictum' that the world is "my idea". (pg340) The idea here is that language is used to express propositions about the world and how the world could be configured, and solipsistic (or realist) propositions are not changing or adding anything intelligible to the language (pg341-2).

The next discussion adds Carnap to the mix, as a representative of the Vienna Circle, which had thoroughly discussed Wittgenstein's Tractatus. Carnap considered the Tractatus to be not entirely free of metaphysics, specifically about the logical structure of propositions/the world. Author investigates what Carnap meant with the term "metaphysics", which firstly was seen as nonsense because it was opposed to verifiability, but later became nonsense because it was the pursuit of external-sentences using language-terms from an internal-language. (pg344-5) Here author claims that Quine's indictment of Carnap's position would be similar to Wittgenstein's. Later, Carnap points out a problem for Wittgenstein: if the solipsist propositions are equivalent to the realist ones, then mustn't their logical form be also equivalent? But even if the propositions can be made into having the same outcomes, their logical form can't be equivalent (author and Carnap argues), thus a tenet of the Tractatus falls (pg346-7).

Author then moves to Reichenbach and his analysis of the "choice" of either the realist language or an "egocentric language". Reichenbach justifies our use of the realist language because it helps justify a great many human actions, like buying life insurance (pg347-8). Author believes this "egocentric language" is a stand-in for Carnap's solipsistic one. Author also argues that it is unlikely this "egocentric language" is even intelligible. (pg349) This leads to an interesting approach to the private language argument in the later Wittgenstein; though author first talks about Wittgenstein's notion how a logic and grammar may be "rotated" around the real need to understand, e.g. intention (pg350-1).