Unfortunately for ethical egoism, the claim that we will all be better off if every one of us does what is in his or her own interest is incorrect. This is shown by what are known as "prisoner's dilemma" situations, which are playing an increasingly important role in discussions of ethical theory... At least on the collective level, therefore, egoism is self-defeating - a conclusion well brought out by Parfit in his aforementioned Reasons and Persons.

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.

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.

There are many cases in which gifted children have done great things without special school programs. There are also gifted kids who have been to special schools and achieved nothing that has benefited the world as a whole. Without solid evidence, I have no confidence that funding school programs for the intellectually gifted would do more good than the most cost-effective programs to help people in extreme poverty.

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.

The future of the world depends on how well we meet it.

At present scientists do not look for alternatives simply because they do not care enough about the animals they are using.