Suppose that there's a gene that makes you gay if you were bottle-fed but that has some completely different effect if you were breast-fed. So in the days before bottles were invented that gene would not have manifested itself as gay behavior, but now that bottles are common it can do so.

Show me a cultural relativist at 30,000 feet and I'll show you a hypocrite ... If you are flying to an international congress of anthropologists or literary critics, the reason you will probably get there - the reason you don't plummet into a ploughed field - is that a lot of Western scientifically trained engineers have got their sum right.

It can be consoling to think your children are in heaven. You have got to understand that that doesn't make it true. Many people cannot understand that distinction.

Our brains have evolved to help us survive within the orders of magnitude of size and speed which our bodies operate at. We never evolved to navigate in the world of atoms.

Public sharing is an important part of science.

There is something infantile in the presumption that somebody else has a responsibility to give your life meaning and point… The truly adult view, by contrast, is that our life is as meaningful, as full and as wonderful as we choose to make it.

I need to learn not to bend over backwards to be nice to faith-heads. Give these people an inch and they take a league. I think, as I did when I wrote The God Delusion, that the Roman Catholic Church is a disgusting institution, the second most evil religion in the world.