6. The Ontological Argument

Ok, this one is an argument that I find slightly more convoluted, but if you're happy to jump inside a philosophical thought experiment for a moment, it does make very good sense. 

In 1078, a Christian monk from Canterbury called Anselm argued that:

"If God POSSIBLY exists, then God ACTUALLY exists."


Actually, as with all good philosophy, I think this argument has some common sense thinking in it that is fairly intuitive when you stop to think about it.

So hang in there!  The video unpacks it for us...


This argument is mainly about the essential nature or definition of God.  God by definition is a "Maximally Great Being", (nothing greater than God) and is ESSENTIALLY:

(ways the world could have been)

So if we're talking about something that fails to be one of these things, then we're not talking about "God" any more, by definition, but rather, something less than God.

If God exists in ANY possible world (ways the world could have been), then he exists in EVERY possible world, including the ACTUAL world.

If this argument is sound, the atheist would have to show that it is IMPOSSIBLE that God exists, because the concept of God isn’t logically incoherent or self-contradictory (like a square circle).

It's a little bit like saying that God, by definition, cannot NOT exist!


1. Do you think it's at least logically POSSIBLE that God exists?  God being:

ALL-POWERFUL (nothing more powerful)
ALL-KNOWING (nothing unknown to him)
MORALLY PERFECT (nothing morally superior)
IN EVERY POSSIBLE WORLD (no world where he could not exist)

Is God an intuitively coherent idea (unlike a square circle or a married bachelor)?

If so, this argument says that God ACTUALLY exists.  What do you make of this logic?

2. Have a look at the summary of the argument below.  How strong do you think the argument is?  Do you think it falls down at any point and if so, where?

3. If the notion of God (as described in this argument) is intuitively coherent and God possibly exists, then it follows that he cannot fail to exist (or he would not be God).  In other words: God essentially exists!  And if anyone says he doesn't, they're talking about something less than God.

Agree or disagree?  Why?

OK, thought experiment over!  Well done!  :)

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