The Circulation Credit Theory of the Trade Cycle (also called the Monetary Theory)

Of all the theories of the trade cycle, only one has achieved and retained the rank of a fully-developed economic doctrine. That is the theory advanced by the Currency School, the theory which traces the cause of changes in business conditions to the phenomenon of circulation credit. All other theories of the crisis, even when they try to differ in other respects from the line of reasoning adopted by the Currency School, return again and again to follow in its footsteps. Thus, our attention is constantly being directed to observations which seem to corroborate the Currency School’s interpretation.

--Ludwig von Mises, On the Manipulation of Money and Credit: Three Treatises on Trade-Cycle Theory, trans. Bettina Bien Greaves, ed. Percy L. Greaves Jr. (Indianapolis: Liberty Fund, 2011), 102-103.