The belief that the animals exist because God created them - and that he created them so we can better meet our needs - is contrary to our scientific understanding of evolution and, of course, to the fossil record, which shows the existence of non-human primates and other animals millions of years before there were any human beings at all.

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.

I honestly don't know, but if America continues to refuse to reduce its greenhouse gas emissions, I see a bleak future not only for American society, but for the world as a whole. This is a global problem that is not going away, and the United States is an obstacle to solving it.

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.

More often there's a compromise between ethics and expediency.

We have a new generation of very rich people who want to do more with their money than buy a lot of expensive toys. They want to live meaningful lives.

The newspapers do little better. Their coverage of nonhuman animals is dominated by "human interest" events like the birth of a baby gorilla at the zoo, or by threats to endangered species; but developments in farming techniques that deprive millions of animals of freedom of movement go unreported.