1 In an artic1e in the Review of Economic Studies, G1ustoff attempts to prove the existence of a Keynesian "equilibrium". The significance of his article tran- scends its explicit purpose of proving existence, since it deals with the more fun- damental question of what is the nature of a Keynesian equilibrium with involuntary unemp1pymant: Moreover, it approaches the problem frPlIl an unorthodox point of view. 4 G1ustoff follows the direction of C1ower,3 who in turn goes back to Morishima and Patinkin;5 that is, unlike the theory based on ex ante demand or supply functions, he redefines the...