Somebody who eats twice as much factory-farmed products as he or she needs to is clearly doing twice as much damage to the planet. From a utilitarian point of view, that's twice as bad.

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.

We certainly would resolve the problems of the charities that are working in areas where they can do the most good. So if you consider that the U.S. foreign aid budget is 30 billion, yes, we could make a major contribution to reducing global poverty, start to deal much better with some of the other big environmental problems that the world faces. So I think we could solve a lot of problems.

We are not especially 'interested in' animals. Neither of us had ever been inordinately fond of dogs, cats, or horses in the way that many people are. We didn't 'love' animals.

My major concern about leaving enhancement to the marketplace is that then the rich will be able to buy themselves genetically superior children and the poor will not - sharpening the class divisions we have now. That problem could be overcome if, genetic enhancement were available to all, subsidized by the state - and that would, over time, have benefits for society as well.

That's a central part of philosophy, of ethics. What do I owe to strangers? What do I owe to my family? What is it to live a good life? Those are questions which we face as individuals.

If we all think only of our own interests, we are headed for collective disaster - just look at what we are doing to our planet's climate.