The Methods of Ethics is a book on ethics by the esteemed English philosopher Henry Sidgwick. The main aim of the book is to provide a systematic account of the principles of commonsense morality. The three general methods of making ethical choices commonly used in ordinary morality are intuitionism (following general principles), egoism (promoting one's own well-being) and utilitarianism (promoting everyone's well-being). According to Sidgwick, intuitionism and utilitarianism are in harmony with each other but egoism cannot be reconciled with utilitarianism, resulting in a "dualism of practical reason".