Marshall made at least four contributions to the classical quantity theory. He endowed it with his Cambridge cash-balance money-supply-and-demand framework to explain how the nominal money supply relative to real money demand determines the price level. He combined it with the assumption of...

Gustav Cassel (1866-1945) deserves credit for establishing quantity-theoretic foundations for Knut Wicksell's (1851-1926) cashless-society version of the cumulative inflationary process and the price-stabilizing policy rule. Wicksell's ambiguities and inconsistencies regarding those foundations...