A 21st Century Ontological Argument: does it work.

[Angrboda]

No, it doesn't.  If it does, then I can conceive of a world without God.  Since I can conceive it, it's possible.  If it's possible, there is one possible world without God.  Since God by definition, if he exists, exists in all possible worlds, then God doesn't exist by implication.  Thanks for playing.

Well played. But incorrect. Why? Because if I'm right, then your second statement is incorrect. You may think you can, but you actually cannot. In other words, someone who doesn't know that Pythagoras' Theorem is a necessary Truth may think he can conceive of a right angled triangle where a2+b2!=c2 where c is the hypotenuse etc, but he actually cannot. He only thinks he can. Thus, likewise, you may think you can conceive of a self-creating world, or a self-existing contingent world, without a Necessarily Existent Creator, but in fact, since His existence is at least possible, therefore it is necessary; in other words, there is no possible contingent world in which the Necessarily Existent Being does not exist.

Thanks for playing.

That's just dumb. How do you know what I can conceive unless you know, not just believe but know, that it's not possible. You don't. All we have is your word that it's not possible. In the same way you think you can conceive of God when in fact you may not be able to only because you have moved the bar to claiming that we can only conceive of things that are possible. In addition to begging the question, this is nonsense. As I can conceive a world where nothing exists, as can Aquinas, and it's not possible for you to show that it's not possible for there to be nothing.

Anyway, I can prove it deductively:

Assume, 1) conceive (X) --> possible (X)
2) by modal logic, conceive(X) --> possible(X) === conceive(X) --> necessarily possible(X)
3) by substitution, conceive(X) --> not possible (not possible(X))
4) I can conceive of a world where the laws of reality forbid X, therefore (possible (not possible(X))
5) by transitivity and 3, (not possible (not possible(X))
6) by transitivity and 5, (possible (not possible(X))
7) by conjunction of 5 & 6, (not possible(not possible(X)) AND (possible(not possible(X))
8) 7 is necessarily false, thus we have a contradiction by assuming 1
Therefore 1 is false.

And in case you need an example where an X cannot occur, you've just given one, a reality that consists of nothing; according to Aquinas, if there is nothing in all possible worlds, then nothing is possible.

As an addendum, you've acknowledged that I'm right, even though you don't admit it. By postulating that my conceived thing must be consistent with other known things, you've shown that conceiving of something, by itself, is not sufficient.

Now, show us that you can conceive of God as necessarily existing without begging the question.