People like to trace their ancestry.

What is the purpose of the universe?" is a silly question.

There may be some deep questions about the cosmos that are forever beyond science. The mistake is to think they are therefore not beyond religion too.

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.

In childhood our credulity serves us well. It helps us to pack, with extraordinary rapidity, our skulls full of the wisdom of our parents and our ancestors. But if we don't grow out of it in the fullness of time, our ... nature makes us a sitting target for astrologers, mediums, gurus, evangelists, and quacks. We need to replace the automatic credulity of childhood with the constructive skepticism of adult science.

We have the same genetic code for all living creatures. We have a large number of genes that are manifestly the same, but with detail differences - they look like different drafts of the same book. In extreme cases, like a human and a beetroot, it's like the difference between Matthew and Luke's Gospel - clearly they tell the same story, but with different words. Whereas with a human and a chimp, it's like two different printings of Matthew, with a few typos in one.

The physicist's problem is the problem of ultimate origins and ultimate natural laws. The biologist's problem is the problem of complexity.