I would not question the sincerity of vegetarians who take little interest in Animal Liberation because they give priority to other causes; but when nonvegetarians say that "human problems come first" I cannot help wondering what exactly it is that they are doing for human beings that compels them to continue to support the wasteful, ruthless exploitation of farm animals.
Peter SingerIf animals are no longer quite outside the moral sphere, they are still in a special section near the outer rim. Their interests are allowed to count only when they do not clash with human interests. If there is a clash - even a clash between a lifetime of suffering for a nonhuman animal and the gastronomic preference of a human being - the interests of the nonhuman are disregarded. The moral attitudes of the past are too deeply embedded in our thought and our practices to be upset by a mere change in our knowledge of ourselves and of other animals.
Peter SingerAccording to classical utilitarianism, the only intrinsic good is happiness; the only intrinsic bad is pain. That implies no intrinsic value in preserving nature, that preserving an endangered plant is valuable only if it benefits humans or other animals. Intuitively, that seems wrong but perhaps I shouldn't trust my intuition here.
Peter SingerSuppose I grant that pigs and dogs are self-aware to some degree, and do have thoughts about things in the future. That would provide some reason for thinking it intrinsically wrong to kill them - not absolutely wrong, but perhaps quite a serious wrong. Still, there are other animals - chickens maybe, or fish - who can feel pain but don't have any self-awareness or capacity for thinking about the future. For those animals, you haven't given me any reason why painless killing would be wrong, if other animals take their place and lead an equally good life.
Peter Singer