The elegant theories of general equilibrium which have been developed during the past three decades leave many economists puzzled, since they appear to have so little to do with real economies.0 Gerard Debreu in his classic Theory of Value states that his theory is concerned with the explanation of prices.1 Yet others as distinguished as Kenneth Arrow and Frank Hahn deny that general equilibrium theories are explanatory.2 In this paper I shall offer a philosophical interpretation of what these mathematical structures called general equilibrium theories are. I shall defend their cognitive worth, although I shall argue that they are virtually without explanatory power.