Don Patinkin and the Pigou effect or how a Keynesian came to adopt an anti-Keynesian argument

International audienceThis paper intends to explain how was a supporter of Keynes like Don Patinkin led to integrate the Pigou effect, the arch anti-Keynesian effect, in his theory of involuntary unemployment. The reading of Patinkin's unpublished PhD thesis and the use of the Don Patinkin Papers from Duke University's archives shed new light on this key episode in the formation of the 'neoclassical synthesis'. Using this material, we show that Patinkin changed his mind on this topic and that his incorporation of the real balance effect into the Keynesian apparatus was, paradoxically, an attempt at reinforcing it