Extreme poverty is not only a condition of unsatisfied material needs. It is often accompanied by a degrading state of powerlessness.
Peter SingerUnfortunately 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.
Peter SingerIf we are prepared to take the life of another being merely in order to satisfy our taste for a particular type of food, then that being is no more than a means to our end.
Peter SingerSo far as this argument is concerned nonhuman animals and infants and retarded humans are in the same category; and if we use this argument to justify experiments on nonhuman animals we have to ask ourselves whether we are also prepared to allow experiments on human infants and retarded adults; and if we make a distinction between animals and these humans, on what basis can we do it, other than a bare-faced - and morally indefensible - preference for members of our own species?
Peter Singer