Цитата из статьи Зингера о всеобщем равенстве:

"In the past, argument about vivisection has often missed the point, because it has been put in absolutist terms: Would the abolitionist be prepared to let thousands die if they could be saved by experimenting on a single animal? The way to reply to this purely hypothetical question is to pose another: Would the experimenter be prepared to perform his experiment on an orphaned human infant, if that were the only way to save many lives? (I say "orphan" to avoid the complication of parental feelings, although in doing so l am being overfair to the experimenter, since the nonhuman subjects of experiments are not orphans.) If the experimenter is not prepared to use an orphaned human infant, then his readiness to use nonhumans is simple discrimination, since adult apes, cats, mice, and other mammals are more aware of what is happening to them, more self-directing and, so far as we can tell, at least as sensitive to pain, as any human infant. There seems to be no relevant characteristic that human infants possess that adult mammals do not have to the same or a higher degree. (Someone might try to argue that what makes it wrong to experiment on a human infant is that the infant will, in time and if left alone, develop into more than the nonhuman, but one would then, to be consistent, have to oppose abortion, since the fetus has the same potential as the infant—indeed, even contraception and abstinence might be wrong on this ground, since the egg and sperm, considered jointly, also have the same potential. In any case, this argument still gives us no reason for selecting a nonhuman, rather than a human with severe and irreversible brain damage, as the subject for our experiments)"

http://www.animal-rights-library.com/texts-m/singer02.pdf