Lots of people talk about “The” Quantity Theory of Money and “The” Equation-of-Exchange. The terms have a familiar feel to them, they’re part of the furniture of Economics. On careful examination, that appearance changes. There isn’t really one Equation-of-Exchange, there are many. One reason for this is that different economists have different ideas about what counts as a transaction and should be included. The Quantity Theory is similar, most of the arguments against it criticise only one version. This is why arguments about these things often descend into confusion.
Anthony Evans and I investigated these problems. We looked at Ludwig Von Mises’ monetary theory and compared it to others. We found that Mises was aiming at something quite different to Fisher, Friedman or present-day quantity theorists. Our paper on this has now been published in the Review of Austrian Economics.
For those lucky people who work in Universities with journal access:
For us plebs without here’s a slightly earlier version: