I speak as a private citizen and not as a representative of the Executive Branch of the United States government. The impression that people of faith are uniformly opposed to stem-cell research is not documented by surveys. In fact, many people of strong religious conviction think this can be a morally supportable approach.

To me, the right approach is to say we are profoundly ignorant of these matters. We need to work on them. But to suddenly say the answer is God - it's that that seems to me to close off the discussion.

Granted, we may try to help our own family members because they share our DNA. Or help someone else in expectation that they will help us later. But when you look at what we admire as the most generous manifestations of altruism, they are not based on kin selection or reciprocity. An extreme example might be Oskar Schindler risking his life to save more than a thousand Jews from the gas chambers. That's the opposite of saving his genes.

I'm fond of science fiction. But not all science fiction. I like science fiction where there's a scientific lesson, for example - when the science fiction book changes one thing but leaves the rest of science intact and explores the consequences of that. That's actually very valuable.

Scientific and technological progress themselves are value-neutral. They are just very good at doing what they do. If you want to do selfish, greedy, intolerant and violent things, scientific technology will provide you with by far the most efficient way of doing so. But if you want to do good, to solve the world's problems, to progress in the best value-laden sense, once again, there is no better means to those ends than the scientific way.

Nowadays theologians aren't quite so straightforward as Paley. They don't point to complex living mechanisms and say that they are self-evidently designed by a creator, just like a watch. But there is a tendency to point to them and say 'It is impossible to believe' that such complexity, or such perfection, could have evolved by natural selection. Whenever I read such a remark, I always feel like writing 'Speak for yourself' in the margin.

Religion is a powerful weapon that can be used because it persuades people to do things. And thus it can be used for good or ill. But it should not be a powerful weapon at all.