A few comments on why it’s a useful discussion:
1. Singer is representative of the modern secular intellectual. Sure, he advocates some highly controversial ethical positions, but his general outlook isn’t fringe. In a sense, he’s only controversial because he’s willing to say openly what he takes to be the logical implications of his worldview. Singer takes for granted the standard naturalistic evolutionary account of human origins. His approach to ethics is a modern, sophisticated version of utilitarianism. He doesn’t have a religious bone in his body, so it would seem, and he doesn’t think there’s the slightest reason to believe in God. I got the impression he could barely conceal his incredulity at Bannister’s views. I suspect he rarely interacts with orthodox Christian intellectuals.
2. Singer trots out the old Euthyphro problem as if it deals a swift death-blow to any divine command theory of ethics, but there’s no evidence that he’s familiar with (or even interested in) the standard responses that have been offered by Christian philosophers. He also thinks the problem of suffering is devastating to any theistic worldview; he can’t begin to understand why an omnipotent, omniscient, omnibenevolent creator would allow the amount and intensity of suffering we find in the world. (Note how much he rests on assumptions about what God would or wouldn’t do. Atheists just can’t help theologizing!) All of this is fairly typical of 21st-century atheist intellectuals: smart and articulate, yet superficial and uninformed in their criticisms of Christian theism.
3. On the whole, Bannister does a fine job in response: a good model for Christian apologists. He’s done his homework. You can tell he’s read Singer’s major works and he’s taken note of shifts in Singer’s views over the course of his career. Bannister is winsome in his demeanor and has a good self-deprecating sense of humor. He’s a clear and effective communicator, deploying some nice illustrations to make his points. He tries to get at the root issues in a serious fashion, rather than trying to score ‘gotcha’ points
4. For my money, the most interesting point that came up in the exchange was this: Singer is still an ethical utilitarian but now describes himself as a moral non-naturalist. A moral non-naturalist thinks there are real moral values that cannot be derived from or reduced to natural (i.e., scientific) facts. Apparently several years ago Singer changed his mind about whether there are objective moral values, i.e., moral norms that are independent of human thoughts, feelings, social conventions, etc. He now thinks there are such values, and his utilitarianism needs to incorporate them in order to bridge the infamous is-ought gap. I take this to be quite a significant concession.
Consequently, what’s striking about this exchange with Bannister is that Singer is operating with two distinct philosophical frameworks, and he subtly shifts back and forth between them depending on the point being pressed. Sometimes Singer answers questions from the standpoint of hard-nosed metaphysical naturalism. There’s no objective meaning or purpose in the universe! The neo-Darwinian evolutionary account of human origins is correct! Modern science has discredited the idea of final causes! Yet at other times — whenever the ethical ‘ought’ questions are posed — Singer adopts his moral non-naturalist stance, helping himself to objective moral norms to which he somehow has epistemic access. He hops from one foot to the other in the blink of an eye, but gives us no idea about how he would integrate these two frameworks in a coherent fashion. How does Singer reconcile his metaphysical naturalism with his moral non-naturalism? We’re left guessing.
To his credit, Bannister picks up on this toward the end and draws a comparison with C.S. Lewis’s intellectual journey from materialism to idealism to deism to theism to Christianity, noting Lewis’s remark that the biggest jump was from materialism to idealism. Bannister somewhat cheekily (but justifiably!) suggested that Singer had slid halfway to idealism. It’s a shame there wasn’t opportunity to explore this point further. Singer has arguably moved to a less consistent position in recent years, faced with the pressure of explanatory gaps in his naturalistic worldview.