principle of equal consideration of interests

The principle of equal consideration of interests (PEC) is a philosophical concept that advocates for giving equal moral weight to the similar interests of all affected beings. This principle, popularized by philosopher Peter Singer, argues that characteristics like race or sex are morally irrelevant when evaluating like interests.1

Singer extends this to animals, asserting that if humans have an interest in avoiding pain, so do animals capable of feeling pain. Therefore, species membership should not be a basis for favoring human interests over animal interests. This challenges speciesism, which is the belief that one species is morally more important than another.1

Arguments against the PEC often suggest that certain capabilities, like rationality or moral agency, are unique to humans and thus morally relevant. However, critics point to "marginal cases"—such as infants or intellectually impaired individuals—where these capabilities are not fully present, creating a dilemma for speciesists. The PEC is a cornerstone of utilitarianism, which seeks to maximize overall happiness and minimize suffering.12