Colin McGinn has written a marvelous essay on “Why I am an Atheist”. He begins by pointing out that the atheist cannot rationally limit his stance to a simple assertion of non-belief: he…
… doesnâ€™t just find himself with a belief that there is no God; he comes to that belief by what he takes to be rational meansâ€”that is, he takes his belief to be justified. He may not regard his atheistic belief as certain, but he certainly takes it to be reasonableâ€”as reasonable as any belief he holds. Just by holding the belief he regards himself as rationally entitled to it (or else he wouldnâ€™t, as a responsible believer, believe itâ€”that being the nature of belief). Also, given the nature of belief, he takes himself to know that there is no God: for to believe that p is to take oneself to know that p. The atheist, like any believer in a proposition, regards his belief as an instance of knowledge (of course, it may not be, but he necessarily takes it to be so). So an atheist is someone who thinks he knows there is no God. Thus he is prepared responsibly to assert that there is no God. The atheist regards himself as knowing there is no God in just the sense that he regards himself as knowing, say, that the earth is round. He claims to know the objective truth about the universe in respect of a divinityâ€”that the universe contains no such entity.
Many theists (and agnostics) protest loudly that such a position is unwarranted, arrogant, and epistemically unreasonable: a an example of the fundamentalism which many atheists criticize in theists. But McGinn will have none of this: theists have exactly the same confident disbelief in many things – other gods, for example – that atheists do. They have no basis for insisting that the atheist should adopt a selective agnosticism:
My state of belief mirrors theirs, except that I affirm zero gods instead of one. (In fact, the idea of many gods has its advantages over the one-god theory: it comports with the complexity of the world and it promotes tolerance.) Yahweh, Baal, Hadad, and Yam: which of these ancient gods do you believe in and which do you think fictitious? I believe in none of them, nor in any others that might be mentioned; if you believe in one of them and disbelieve in the others, then you are just like me with respect to those others. Atheism is not confined to atheists, and the epistemology is the same no matter which gods you disbelieve in.
Having made his case, McGinn confesses that he finds the label of atheist a rather misleading one:
So my state of belief is not that of one continuously denying the existence of God, with an active belief that there is no such entity (though it is true that I am more often in this state than I would be the issue were not constantly debated around me). I am, dispositionally at any rate, in a state of implicit disbelief with respect to Godâ€”as I am in a state of implicit disbelief about ghosts, goblins and Santa. I simply take it for granted that there is no God, instead of constantly asserting it to myself. The state of mind I am in while composing this essay is not then my habitual state of mind, and even to be explicitly denying the existence of God strikes me as taking the issue a little too seriouslyâ€”as it would be to write an essay making explicit my negative implicit beliefs about Santa Claus. So I am really as much post-atheist as post-theist, when it comes to my natural state of mindâ€”just as I suppose most people are post-a-polytheist as well as post-polytheist. Polytheism, for most people, is simply a dead issue, not a subject of active concern. Theism for me is a dead issue, which is why it is misleading to call me an atheist–though it is of course strictly true that I am. It is misleading in just the way it is misleading to speak of a traditional Christian as an a-polytheist or a normal adult as an a-Santa-ist, since it suggests are far more active engagement with the issue than is the case. Many other difficult issues engage my mind and remain unresolved or at least open to serious question, but not my disbelief in God.
He closes with some thoughts about what it might mean for God-talk to remain with us in a purely fictional mode. I’m not holding my breath. All the same, it’s a wonderful essay. (Of course I would say that, wouldn’t I?) If you want to know what I believe, you could do worse than read it.