Posted by zeugma on January 18, 2005, at 18:01:25
In reply to Re: Wittgenstein on thought, posted by alexandra_k on January 17, 2005, at 15:36:12
Oh. Hey, if possible worlds in which a proposition is true and false delineate the meaning of a proposition then there are problems with tautologies and contradictions. The problem is that they would have to mean the same thing or have the same content becasue tautologies are true in all possible worlds and contradictions are true in no possible world. So 2+2=4 and p=p have the same content or meaning. Some people are ok with that (the best defence I have heard was that tautologies and contradictions are actually contentless). Would be interested to know if you are ok with that.>>
Well, I'd rather say that p=p and 2+2=4 have the same content, than that they have no content. They are both identities, and I am reluctant to say that identity-statements are meaningless (and whether they are meaningful but contentless? well,maybe. But is 2+2=4 really a tautology? I suppose we go back to Kant here, and his demonstration that there is nothing in the concepts of '7' and '5' to show that they add up to '12.' But then we're talking about 'concepts',and we're trying to get past that, right? I think that if we use possible worlds as a model for content, then we have to say that all necessary propositions are one and the same. I don't necessarily have a problem with that. But it is puzzling. And we had better get an account of how it is that p=p is easy but it gets harder from there.)
I think admitting the spade has turned is something a philosopher has to say, at some point. About mental processes: we can say that their 'hiddenness' isn't interesting. (The opposite seems true, but anyway...) Now I have a question for you. behaviorism is a kind of 'anti-realism' about the mind. it says there's nothing there, nothing that can't be captured equally well by the exhaustive physical analysis we can't perform yet and probably never will. Now Wittgenstein denied he was a behaviorist (or am I thinking of someone else here?). It seems that one influence of Wittgenstein is to turn philosphers in an anti-realist direction. I read that Wittgenstein came back to philosophy by hearing about Heyting's lectures elaborating intuitionism in mathematics (a turn away from the realism of the Frege-Russell tradition). Intuitionism is a step is a constructivist direction, a way of giving sense to mathematical discourse by constructing proofs, and I believe they upheld the Law of Excluded Middle, in which a statement could not be simulataneously true AND false, but denied the Principle of Bivalence, according to which all statements must be either true or false (excluding for the moment vague predicates,and which I am in the process of trying to figure out..agg) because unless one could construct a proof, one could not assign a truth-value to it. This seems to be an example of 'hygiene' which keeps our mathematical discourse in order, because we either can construct the proof, in which case we KNOW the discourse has sense because it's true, and also lets us know when we're venturing into regions where our hold on sense becomes perilous. Anyway, that's just my thought. I've heard it said that Wittgenstein was a more radical constructivist than these intuitionist mathematicians, because Heyting had an essentially Kantian idea of 'intuition' (which is a topic of its own to contend with!) whereas Wittgenstein obviously discards the kantian language of 'synthetic' and 'analytic' and so forth.-z
poster:zeugma
thread:436252
URL: http://www.dr-bob.org/babble/write/20050118/msgs/443844.html