Some sort of belief in all-powerful supernatural beings is common, if not universal. A tendency to obey authority, perhaps especially in children, a tendency to believe what you're told, a tendency to fear your own death, a tendency to wish to see your loved ones who have died, to wish to see them again, a wish to understand where you came from, where the world came from, all these psychological predispositions, under the right cultural conditions, tend to lead to people believing in things for which there is no evidence.

People will listen to sophisticated physicists, using God as a kind of metaphor for the deep constants, the deep problems, the deep principles of physics, and say that in that sense I believe in God. The reaction is, "Oh, this great physicist believes in God - that means I'm free to believe in the trinity and in the crucifixion and in the reincarnation of Christ" - and all that stuff, which of course has nothing whatever to do with the fundamental constants of physics, which is what these physicists are talking about.

Religion has been a powerful weapon in the hands of governments, in the hands of priests, in the hands of kings who have used it as a weapon to keep down the populace. It is a wonderful way of disciplining people and making them do what you want, to tell them that if they don't do what you want they will, for example, go to Hell.

The other way is the multiverse way. That says that maybe the universe we are in is one of a very large number of universes. The vast majority will not contain life because they have the wrong gravitational constant or the wrong this constant or that constant. But as the number of universes climbs, the odds mount that a tiny minority of universes will have the right fine-tuning.

People will say, "You're never going to convince me that something as complicated as an eye could come about by sheer chance." And the answer is that natural selection is the very opposite of sheer chance. Natural selection is a non-random process.

Natural selection, the blind, unconscious, automatic process which Darwin discovered, and which we now know is the explanation forthe existence and apparently purposeful form of all life, has no purpose in mind. It has no mind and no mind's eye. It does not plan for the future. It has no vision, no foresight, no sight at all. If it can be said to play the role of the watchmaker in nature, it is the blind watchmaker.

Book critics or theatre critics can be derisively negative and gain delighted praise for the trenchant with of their review. But in criticisms of religion even clarity ceases to be a virtue and sounds like aggressive hostility. A politician may attack an opponent scathingly across the floor of the House and earn plaudits for his robust pugnacity. But let a soberly reasoning critic of religion employ what would in other contexts sound merely direct or forthright, and it will be described as a 'rant'.