The problem is that no ethical system has ever achieved consensus. Ethical systems are completely unlike mathematics or science. This is a source of concern.

The only answer to the endless chains of why, why, why is that the alternatives died

I think that what one can see from a Darwinian account is how the addition of culture in our species turns us into a very special sort of animal, an animal that can be a moral agent in a way that no other animal can be.

The earth has grown a nervous system, and it's us.

I listen to all these complaints about rudeness and intemperateness, and the opinion that I come to is that there is no polite way of asking somebody: have you considered the possibility that your entire life has been devoted to a delusion? But that’s a good question to ask. Of course we should ask that question and of course it’s going to offend people. Tough.

Sometimes you don’t just want to risk making mistakes; you actually want to make them - if only to give you something clear and detailed to fix.

Has it ever occurred to you how lucky you are to be alive? More than 99 percent of all the creatures that have ever lived have died without progeny, but not a single one of your ancestors falls into that group! ... Not a single one of your ancestors, all the way back to the bacteria, succumbed to predation before reproducing, or lost out in the competition for a mate.