I became a little alarmed at the number of my readers who took the meme more positively as a theory of human culture in its own right - either to criticize it (unfairly, given my original modest intention) or to carry it far beyond the limits of what I then thought justified. This was why I may have seemed to backtrack.

I think nobody would claim that random genetic drift is capable of producing adaptation, that is to say the illusion of design. Random genetic drift can't produce wings that are good at flying, or eyes that are good at seeing, or legs that are good at running. But random genetic drift probably is very important in driving evolution at the molecular genetic level.

The assignment of purpose to everything is called teleology. Children are native teleologists, and many never grow out of it.

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.

I am agnostic only to the extent that I am agnostic about fairies at the bottom of the garden

Or why it is acceptable to train fast runners and high jumpers but not to breed them. I can think of some answers, and they are good ones, which would probably end up persuading me. But hasn't the time come when we should stop being frightened even to put the question?

I am not an enthusiast for diversity of opinion where facts are concerned.