Today, if you have an Internet connection, you have at your fingertips an amount of information previously available only to those with access to the world's greatest libraries - indeed, in most respects what is available through the Internet dwarfs those libraries, and it is incomparably easier to find what you need.

Typically, defenders of experiments on animals do not deny that animals suffer. They cannot deny the animals' suffering, because they need to stress the similarities between humans and other animals in order to claim that their experiments may have some relevance for human purposes. The experimenter who forces rats to choose between starvation and electric shock to see if they develop ulcers (which they do) does so because the rat has a nervous system very similar to a human being's, and presumably feels an electric shock in a similar way.

Whatever the reason, for most of the present century, the literature and publicity of the old established [animal welfare] groups made a significant contribution to the prevailing attitude that dogs and cats and wild animals need protection, but other animals do not. Thus people came to think of "animal welfare" as something for kindly ladies who are dotty about cats, and not as a cause founded on basic principles of justice and morality.

The notion that human life is sacred just because it is human life is medieval.

When you look at food as an ethical issue in the Christian tradition, you don't find very much about it. You don't find, as you do in the Jewish or Islamic or Hindu traditions, a lot of restrictions saying you can eat this but you can't eat that. But what you do find is the idea that gluttony is a sin and that it's something that we ought to be ashamed of.

I do not believe that it could never be justifiable to experiment on a brain-damaged human.

If you have the abilities to earn a lot of money and if you have the character to persist in giving that to the most effective charities you can find, then that may be the best thing that you can do. And - also, if you do become a Wall Street banker, I think you need to be aware of what you're doing in terms of your daily work, not just earning money to give a lot away. But you need to think about - am I harming people through the work that I'm doing?