Classical economics suggests that market economies are self-correcting in times of recession or depression, and tend toward full employment and output. But English economist John Maynard Keynes disagrees. In his ground-breaking 1936 study The General Theory, Keynes argues that traditional economics has misunderstood the causes of unemployment. Employment is not determined by the price of labor; it is directly linked to demand. Keynes believes market economies are by nature unstable, and so require government intervention. Spurred on by the social catastrophe of the Great Depression of the 1930s, he sets out to revolutionize the way the world thinks about and understands economics