Were we incapable of empathy – of putting ourselves in the position of others and seeing that their suffering is like our own – then ethical reasoning would lead nowhere. If emotion without reason is blind, then reason without emotion is impotent.

One thing is certain: you will find plenty of worthwhile things to do. You will not be bored, or lack fulfillment in your life. Most important of all, you will know that you have not lived and died for nothing, because you will have become part of the great tradition of those who have responded to the amount of pain and suffering in the universe by trying to make the world a better place.

It is easy for us to criticize the prejudices of our grandfathers, from which our fathers freed themselves. It is more difficult to distance ourselves from our own views, so that we can dispassionately search for prejudices among the beliefs and values we hold

If they [animals] were really to get the equal consideration that I believe they should, we wouldn't have commercial animal production in this country.

Human decision-making is complex. On our own, our tendency to yield to short-term temptations, and even to addictions, may be too strong for our rational, long-term planning.

If possessing a higher degree of intelligence does not entitle one human to use another for his or her own ends, how can it entitle humans to exploit non-humans?

We wait until Pandora's box is opened before we say, "Wow, maybe we should understand what's in that box." This is the story of humans on every problem.