Was Patinkin a Keynesian Economist?

Don Patinkin regarded himself a Keynesian economist, in the sense that he did not believe that the automatic market mechanism of price change efficiently leads the economy to its full-employment path. In his 1956 Money, Interest and Prices Patinkin advanced an interpretation of Keynesian macroeconomics as disequilibrium economics. However, he was perceived as an anti-Keynesian economist by a substantial part of the profession. The present essay discusses why was that so, based on an investigation of the "central message" of Patinkin's theoretical framework and on unpublished archive material. Frankly, I have never been able to understand why my Money, Interest, and Prices was regarded in some circles as an anti-Keynesian work. I have always regarded it as a work that strengthened the Keynesian view by diverting attention from the pointless semantic issue of whether there could or could not exist a situation of "unemployment equilibrium", to the real question of the efficacy of price flexibility in restoring full employment. (Letter from Don Patinkin to James Tobin, 1 Jan 1992; Duke University, Don Patinkin Papers).