Painism is a moral theory popular with animal rights theorists. It states that moral action should be based on reducing the pain of individuals, and furthermore, that pain cannot be aggregated; that is, painism rejects utilitarianism. Painism also rejects evaluations of pain based on intelligence, rationality, or degrees of consciousness. The capacity to feel pain is regarded as the only morally relevant factor.
The term was first used by British psychologist Richard D. Ryder, who also coined the term speciesism.