So why don't we make ourselves the last generation on earth? If we would all agree to have ourselves sterilized then no sacrifices would be required - we could party our way into extinction!

There is an obvious evolutionary explanation for the scarcity of altruistic saints: Without a strong predilection for their own interests, our ancestors would have been unlikely to survive, reproduce, and give their own offspring a chance of doing the same. Now conditions have changed and for most of us, surviving and reproducing isn't such a struggle but we still carry the genes of our ancestors and they influence - not determine, but influence - our behavior.

I believe that nationalism is a very strong force, but there are other forces operating; there are tendencies pushing towards a larger picture, especially in Europe, I think; but I still think nationalism is real.

Personal purity isn’t really the issue. Not supporting animal abuse – and persuading others not to support it – is.

So why don't we make ourselves the last generation on earth? If we would all agree to have ourselves sterilized then no sacrifices would be required - we could party our way into extinction!

With the eventual acceptance of Darwin's theory we reach a modern understanding of nature, one which has since then changed in detail rather than in fundamentals. Only those who prefer religious faith to beliefs based on reasoning and evidence can still maintain that the human species is the special darling of the entire universe, or that other animals were created to provide us with food, or that we have divine authority over them, and divine permission to kill them.

Probability is the guide of life, and of death, too.