20 October 1866|
|Died||14 January 1945
|Alma mater||Uppsala University|
|Contributions||Purchasing power parity,
work on interest
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(central europe). 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.
Apart from the rudiments of a purchasing power parity theory of exchange rates (1921), he produced an 'overconsumption' theory of the trade cycle (1918). He also worked on the German reparations problem. He was a member of many committees dealing with matters of state in Sweden and devoted much labour to the creation of a better system of budget exposition and control (1905–21). He was one of the Swedish representatives at the International Chamber of Commerce meeting in London in 1921. He became a member of Svenska Vetenskapsakademien and correspondent for Sweden to the Royal Economic Society.
In addition to his books in Swedish, he published the following works in other languages: Das Recht auf den vollen Arbeitsertrag (1900), The Nature and Necessity of Interest (1903), Theoretische Sozialökonomie (1919). His Memorandum on the World's Monetary Problems, published by the League of Nations for the International Financial Conference in Brussels in 1920, attracted widespread attention.
- Cassel, Gustav. The Theory of Social Economy. New York: Augustus M. Kelley, 1967.
- "Gustav Cassel (1866–1945)". The Concise Encyclopedia of Economics. Library of Economics and Liberty (2nd ed.) (Liberty Fund). 2008.