Sometime ago, over at Unqualified Offerings, I plunged into a thread where some atheists were contending that suggesting there is some link between the existence of genuine moral standards and the existence of God is just absurd. I argued that they were, in fact, confused, because acknowledging the existence of universal moral principles already is acknowledging the existence of God, since, in the Western metaphysical tradition, that is what the word God means. I was greeted with howls of execration (what's that from?) and accused of just making definitions up to suit my purposes. I cited Collingwood in my defense, but this was unconvincing.
I now wish to call another witness to the stand. I've been reading Augustine's On Free Choice of the Will, in which he leads "Evodius" to acknowledge that the fact that we have rational standards by which we judge, say, that "2 + 2 = 4" alone is sufficient to show the existence of God, because the existence of such rational standards is what is meant by the term "God." Yes, of course, in mainstream Christian theology much more than that is meant, but remember that Augustine, even after his conversion, is still very much a Platonist, and he recognizing that in this metaphysical tradition, the name for the "universal light of reason" is God. Once someone has admitted that there are universal standards to which we must submit if we want to reason correctly, speak truthfully, behave justly, etc., the argument about the mere existence of God is over, if not that about God's full nature.
So there you have it, folks -- if you admit that arithmetic is universally true for all rational beings, you are not an atheist. You may call yourself one, but you are mis-using the term in the light of the tradition of Western metaphysics. (Einstein, for instance, recognized this very well, which is why so many atheists keep trying to dismiss all of his statements about God as "really just about the rational order of the universe"... well, precisely!
In the first comment I've pasted in a sample of Augustine's dialogue, just so you can see I'm not making this up. Note carefully the point he is making at the end -- he's not saying that, once you admit there are universal standards of truth, then you must admit there is something else besides and separate from those standards called God -- no, he's saying the proper name (in our philosophical tradition) for such a standard is 'God.'