In the past 20 years alone, it adds up to more death than were caused by all the civil and international wars adn government repression of the entire twentieth century, the century of Hitler and Stalin. How much would we give to prevent those horrors? Yet how little are we doing to prevent today's even larger toll and all the misery that it involves? I believe that if you read this book to the end, and look honestly and carefully at our situation, assessing both the facts and the ethical arguments, you will agree that we must act.

The new freedom of expression brought by the Internet goes far beyond politics. People relate to each other in new ways, posing questions about how we should respond to people when all that we know about them is what we have learned through a medium that permits all kinds of anonymity and deception.

The traditional view of the sanctity of human life will collapse under pressure from scientific, technological and demographic developments.

To be a utilitarian means that you judge actions as right or wrong in accordance with whether they have good consequences. So you try to do what will have the best consequences for all of those affected.

If penicillin had been judged by its toxicity to guinea pigs, it might never have been used by man.

Suppose I grant that pigs and dogs are self-aware to some degree, and do have thoughts about things in the future. That would provide some reason for thinking it intrinsically wrong to kill them - not absolutely wrong, but perhaps quite a serious wrong. Still, there are other animals - chickens maybe, or fish - who can feel pain but don't have any self-awareness or capacity for thinking about the future. For those animals, you haven't given me any reason why painless killing would be wrong, if other animals take their place and lead an equally good life.

I suppose what's happened recently has confirmed suspicions I voiced in the book, and I think made clearer some of those things that I point out. For instance I have a section of the book where I talk about the possibility of torture.