Norm at Normblog quotes from article by John Meacham:
So is God real? It seems safe to say at least this much: he is real insofar as he is a force who influences human beings who believe in his existence. In his landmark Gifford Lectures at Edinburgh in 1901, the American philosopher William James quoted a Bryn Mawr colleague on the matter: "The truth of the matter can be put in this way: God is not known, he is not understood; he is used - sometimes as a meat-purveyor, sometimes as moral support, sometimes as friend, sometimes as an object of love. If he proves himself useful, the religious consciousness asks for no more than that. Does God really exist? How does he exist? What is he? are so many irrelevant questions. Not God, but life, more life, a larger, richer, more satisfying life, is, in the last analysis, the end of religion."
But, says Norm, 'real insofar as he is a force who influences human beings who believe in his existence' is obviously a question-begging trick: unless God actually does exist, the force that influences those who believe in his existence is not God but their belief in him. So God is either really real or he isn't real at all. There's no middle way in which God is real insofar as. As for the William James quote, I have no wish to appear disrespectful, but the same line of argument might equally be used to establish the validity of the idea of the Tooth Fairy.
My own difference with Norm here may be put in the form of a question. Why do we assume that no matter what the subject matter - trees, money, love, God - we can always draw the distinction between the real and the unreal in the same way? How would we go about distinguishing between a real and an unreal tree, money, love, God? Surely it is in the different ways in which we go about this that we come to appreciate the notions of reality involved. We do not know, free of any context, what the distinction between the real and the unreal comes to, and the context in which to consider the reality of God is the collection of beliefs and practices that we call religion.