dexlargo

I looked through this thread briefly, and am sad that I am so late to the party. There are a number of mistakes made with respect to possible world semantics. But the problem is in the accessibility relation that is defined between the worlds. If we are to assume that every world is accessible from every other world, then it is true that if some statement is necessarily true at one world, then it is true at every other world. But only if our accessibilty relation is defined this way.

When I was studying modal logic, we looked into this problem, and the only thing that can be concluded, using first order modal logic at least, is that if god possibly exists, then god exists necessarily. Or in longhand: if there is a possible world in which god exists, then god exists in every possible world. We can conclude that, but you still have to show me that there is a possible world in which god exists.