Is there morality without God? This was the topic which I debated with Princeton philosopher Peter Singer on the Riz Khan show on Al-Jazeera Monday. The segment is now up on the web and you can watch it here.

No, I haven't signed on as an Al-Jazeera regular. But the producers of the Riz Khan show on that network seemed a bit disappointed when Richard Dawkins agreed to appear on their show but then threw a tantrum when he found out he was scheduled to debate me. Instead Dawkins insisted on separate segments, with him going second, so that I wouldn't have a chance to challenge his arguments.

Singer is a much braver soul, and truth be told, he strikes me as more articulate and versatile than Dawkins. I suspect the only reason Singer isn't more of an atheist hero is because his social positions are so controversial. Basically Singer has declared that newborns have no rights and can be killed off during the first few weeks of their life, and he would vastly liberalize the rules for infanticide and euthanasia. Singer and I will be debating all this on December 3 at Princeton University. By all means come, but perhaps you should leave the grandparents at home.

In the Al-Jazeera exchange, Singer echoed a theme sounded by some of the street interviews: we don't need God to be good. And in this sense, who can disagree? Of course atheists can be kind and truthful and keep their oaths and contracts. No one is saying that Christians have a monopoly on virtue, or that unbelievers are incapable of it.

Rather, the deeper point is that morality seems built into human nature, and it doesn't have an adequate Darwinian explanation. Singer, an ardent Darwinist, admits this. He said on the show that evolution tells us what we are but it doesn't tell us anything about how we should be. Dawkins too writes that he is Darwinian in his biology but anti-Darwinian in his ethics. According to Dawkins, biology programs selfishness into our genes but we can rise above all that and behave unselfishly. Yet as I pointed out on the show, ants and cheetahs cannot do this. It makes no sense to say, "Bad cheetah! You shouldn't chase after that nice antelope." So where do we evolved primates get this other capacity that frequently operates against our self-interest? This is at least worth reflecting on.

One caller provoked Singer's derision by suggesting that even atheist philosophers get their morality from religion. Singer responded that this was factually wrong. He noted that John Stuart Mill and Jeremy Bentham weren't religious. True, but their utilitarianism is based on the principle of equal respect for human beings, and that is a principle that came into the West because of Christianity. Singer attempted to deny this. He tried to locate this Western egalitarianism in Epictetus and Marcus Aurelius, but he offered nothing to substantiate this far-fetched claim. If there were historians watching the show, I am sure they were shaking their heads. Certainly the American founders didn't get "all men are created equal" from the sayings of Epictetus or the meditations of Aurelius. By their own account, they attributed our egual dignity and our inalienable rights to the "Creator."

I'm looking forward to exploring this topic in greater detail with Singer on his home campus in December. But before that, I have my third debate with Christopher Hitchens coming up September 10 in St. Louis. As Hitchens himself put it, all our debates are different because each time we get better at countering what the other guy said the last time. If you'd like to find out more and get tickets, you can do so here.