Gustav Cassel

Karl Gustav Cassel (20 October 1866 – 14 January 1945) was a Swedish economist and professor of economics at Stockholm University.

Cassel's perspective on economic reality, and especially on the role of interest, was rooted in British neoclassicism and in the nascent Swedish schools. He is perhaps best known through John Maynard Keynes' article Tract on Monetary Reform (1923), in which he raised the idea of purchasing power parity.

"Cassel was beyond doubt one of the outstanding figures in economic science during the inter-war period. His authority was second only to that of Lord Keynes, and his advice was eagerly sought on many occasions by his own Government and by foreign Governments."

He was also a founding member of the Swedish school of economics, along with Knut Wicksell and David Davidson. Cassel came to economics from mathematics. He earned an advanced degree in mathematics from Uppsala University and was made professor at Stockholm University during the late 1890s but went to Germany before the turn of the century to study economics, publishing papers spanning just under forty years.