Principia Ethica is a 1903 book by the British philosopher G. E. Moore, in which the author insists on the indefinability of "good" and provides an exposition of the naturalistic fallacy. Principia Ethica was influential, and Moore's arguments were long regarded as path-breaking advances in moral philosophy, though they have been seen as less impressive and durable than his contributions in other fields.
Summary
Moore insists that "good" is indefinable, and provides an exposition of what he calls the "naturalistic fallacy." He defends the objectivity and multiplicity of values, arguing that knowledge of values cannot be derived from knowledge of facts, but only from intuition of the goodness of such states of affairs as beauty, pleasure, friendship and knowledge. In Moore's view, right acts are those producing the most good.
Reception
Principia Ethica was influential, and helped to convince many people that claims about morality cannot be derived from statements of fact. Clive Bell considered that through his opposition to Spencer and Mill, Moore had freed his generation from utilitarianism. Principia Ethica was the bible of the Bloomsbury Group, and the philosophical foundation of their aesthetic values. Leonard Woolf considered that it offered a way of continuing living in a meaningless world. Moore's aesthetic idea of the organic whole provided artistic guidance for modernists like Virginia Woolf, and fed into Bell's concept of Significant form. Principia Ethica also had a powerful influence on modernism through the anti-empiricism of T. E. Hulme. Socioculturally, a line can be traced from Principia Ethica to the liberal thought of Roy Jenkins, as evidenced in his 1959 pamphlet Is Britain Civilised? and actuated in his subsequent Home Office reforms which established much of the institutional framework for the permissive society in England. Moore's ethical intuitionism has been seen as opening the road for noncognitive views of morality, such as emotivism. C. P. Snow sketched the enduring influence of Moore on his followers' group-belief in pleasure: "They tried to get the maximum of pleasure out of their personal relations. If this meant triangles or more complicated geometrical figures, well then, one accepted that too....If you didn't believe in pleasure, you couldn't be civilized". In A Theory of Justice, John Rawls compares Moore's views to those of Hastings Rashdall in his The Theory ofGood and Evil. Moore's views have also been compared to those of Franz Brentano, Max Scheler, and Nicolai Hartmann. Principia Ethica has been seen by Geoffrey Warnock as less impressive and durable than Moore's contributions in fields outside ethics. John Maynard Keynes, an early devotee of Principia Ethica, would in his 1938 paper 'My Early Beliefs' repudiate as Utopian Moore's underlying belief in human reasonableness and decency.
