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.

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.

Nature is not cruel, only pitilessly indifferent. This is one of the hardest lessons for humans to learn. We cannot admit that things might be neither good nor evil, neither cruel nor kind, but simply callous-indifferent to all suffering, lacking all purpose.

If you set out in a spaceship to find the one planet in the galaxy that has life, the odds against your finding it would be so great that the task would be indistinguishable, in practice, from impossible.

Evolution could so easily be disproved if just a single fossil turned up in the wrong date order. Evolution has passed this test with flying colours.

There is great variation in brain power all the way from Einstien on one hand to Sarah Palin on the other.

The fact that somebody does good doesn't make their beliefs true.