"The Methods of Ethics" by Henry Sidgwick is a philosophical work first published in 1874. This landmark treatise examines how people make moral decisions, identifying three distinct approaches: intuitionism, egoism, and utilitarianism. Through meticulous analysis, Sidgwick explores whether these methods can coexist harmoniously or inevitably clash. His investigation reveals surprising compatibilities and troubling contradictions within our moral reasoning, ultimately uncovering what he calls a "dualism of practical reason" that challenges the foundations of ethical thought. (This is an automatically generated summary.)