Up until a few minutes ago I agreed, at least in principle, with his stance. That is, I accepted that atheism is a metaphysical belief and as a belief it cannot be entirely rational.
In fact I've always had a counter-argument in my back pocket. As a scientist I'm allowed (and possibly required) to invoke Occam's razor. Since modern physics strongly suggests that we don't need God, simplicity requires that we should just do away with him altogether and move on to something more productive like game theory.
Which I did. And as I was mucking about with a payoff matrix relating to a Limit Holdem situation on the turn, it suddenly occurred to me that I was being far too wishy-washy with this God business.
Part of the difficulty here is defining exactly what it is that I don't believe in. The American Evangelist has a very different God than a liberal British Anglican. The former is the traditional, Old Testament law-giving lunatic that I (and Jesus) have described elsewhere, whereas the latter is a sort of bake-sale supervisor who no longer likes to show off the fact that he has ultimate power and dominion over everything. I see no point in worrying about pantheistic traditions. If God is in a stone and this has absolutely no impact on how the stone behaves then I really can use Occam's razor to zap that deity into meaninglessness.
It seems to me that any God worth believing in must be omnipotent, omniscient, and in some sense supernatural. "Supernatural" pretty much reduces to "creator of the Universe" since anything else would put God within the Universe and thus subject to physical inquiry and explanation. And if you created the Universe it follows you can tweak its behavior whenever you choose.
So we can't build a Godometer and attempt to detect The Almighty, but we can look at his handiwork and the way he maintains it to address the question of whether his existence is plausible. And this gets us into the heart of theology.
Theologians through the ages have devoted their lives to the question of why God allows such horrors to afflict his children. They have come up with exquisite schemes involving original sin and free will and heaven and hell. And... okay maybe I'm missing something, but isn't it all complete bullshit? It seems to me the complex stories these people weave are desperate smoke-and-mirrors routines that attempt to divert attention from something rather obvious.
Put yourself in God's shoes for a moment. You see a human being battering a cat with a baseball bat. What would you do? Not only are you all powerful, you have infinite mercy. Give me one sane reason why you wouldn't stop the human crushing the skull of the cat?
There isn't one. But God doesn't save the cat.
And that is why millions of people have written billions of words on God's refusal to prevent suffering, and why the major religions can't agree on The Answer. There cannot be an answer when the premise is false.
The cat is not saved because there is no God. Any other conclusion is irrational.