I can't be sure God does not exist... On a scale of seven, where one means I know he exists, and seven I know he doesn't, I call myself a six... That… - Richard Dawkins

We should be offended when children are denied a proper education. We should be offended when children are told they will spend eternity in hell. We should be offended when medical science, for example stem-cell research, is compromised by the bigoted opinions of powerful and above all well-financed ignoramuses. We should be offended when voodoo, of all kinds, is given equal weight to science. We should be offended by hymen reconstruction surgery. We should be offended by 'female circumcision', euphemism for genital mutilation. We should be offended by stoning.

More generally, as I shall repeat in Chapter 8, one of the truly bad effects of religion is that it teaches us that it is a virtue to be satisfied with not understanding.

When we look at a solid lump of iron or rock, we are 'really' looking at what is almost entirely empty space. It looks and feels solid and opaque because our sensory systems and brains find it convenient to treat it as solid and opaque. It is convenient for the brain to represent a rock as solid because we can't walk through it. 'Solid' is our way of experiencing things that we can't walk through or fall throug, because of the electromagnetic forces between atoms. 'Opaque' is the experience we have when light bounces off the surface of an object, and none of it goes through.