St. Thomas defines logical possibility as the non-repugnance of a predicate to a subject. Interestingly, he denies that it is a sort of possibility at all, real or otherwise, even analogously (STA says that this sort of thing is a “possibility” only by metaphor). Modern and contemporary philosophers have largely ignored him, and now it is common for us to think that X is really possible because we can see no contradiction in it or because we can imagine it being the case.
As soon as we start thinking that logical possibility is real possibility, we come to believe that our inability to see a contradiction in something bespeaks some real possibility that must be dealt with. We think we are in the position of being unable to count out the possibility of X because we see no contradiction in X. All of a sudden, an infinitude of things become really possible; universes of possible worlds spring up; and we are stuck at every turn thinking that we have to do something to rule out some “real possibility” in things.
Paul Hamilton said,
November 4, 2009 at 1:16 pm
Have you read James Ross’ recent book “Thought and World”? I am beginning to read it, and he addresses this topic in quite a bit of detail.