Friday, 2 January 2015

Conceivability of the GCB

Some argue that conceiving of something isn't as foolproof as we might typically think. This is a common response to Chalmer's philosophical zombie argument. When you're conceiving of a philosophical zombie, how do you know you're not really just thinking about a conscious person? What is different about the two conceptions? Is it that, in the one case, you're saying in your mind 'this thing is not conscious'? But surely being able to simply describe something doesn't amount to conceiving of it: even machines can do that. Indeed, we can even describe inconsistent scenarios, but it's odd to say such things can be conceived of.

It's like trying to conceive of a transparent block of iron. Close your eyes, can you do it? Once you've managed to conjure up an image, ask yourself; how do I know this isn't really just a block of glass?

Now turning to theological matters: how do you know you're thinking of the greatest conceivable being? Is it simply because you're saying in your head, "this thing is greater than anything else I could conceive"? Indeed, how do you know it's not the second or third greatest, rather than the first? It seems Anselm's God is like the transparent iron, or the philosophical zombie: even if such a thing is conceivable, we don't have good reason to believe it.