Just as oppressed people suffer from discriminatory beliefs and attitudes—women from sexism, people of color from racism, gay people from homophobia—so too, says the Australian philosopher Peter Singer (1946–), do animals suffer from “speciesism.” Speciesism is the belief that one particular animal species—the human species—is innately superior to all others. This supposed superiority leads humans to engage in the morally unjustifiable oppression, exploitation, and slaughter of other species. According to Singer, who is a professor of philosophy at Princeton University, the aim of the animal liberation movement is to expose, criticize, and overcome these widely shared speciesist attitudes.