At the same time I have noted that some of the differences between the public and private sector may have been exaggerated they are differences among… - Joseph E. Stiglitz

The theories that I (and others) helped develop explained why unfettered markets often not only do not lead to social justice, but do not even produce efficient outcomes. Interestingly, there has been no intellectual challenge to the refutation of Adam Smith’s invisible hand: individuals and firms, in the pursuit of their self-interest, are not necessarily, or in general, led as if by an invisible hand, to economic efficiency. The only question that has been raised concerns the ability of government to remedy the deficiencies of the market. Within academia, a significant fraction of economists are involved with developing and expanding on the ideas of imperfect information (and imperfect markets) that I explored. For instance, Edmund Phelps, this year’s Nobel Prize winner, belongs to this "school" of thought. But in political discourse, simplistic “market fundamentalism” continues to exert enormous influence.

Competition is limited by the scale of the market, and as the scale of the market has changed, so has the effectiveness of competition.

In short, whether for the obvious reason that in the absence of futures markets the price system cannot perform its essential coordinating role with respect to future-oriented activities, such as investments, or for the more subtle reasons just discussed, that in the absence of futures markets, extending infinitely far into the future, the market economy is likely to exhibit dynamic instabilities there is no reason to believe that even with rational expectations it will converge to the steady state; there is no presumption that markets, left to themselves, will be efficient. For advocates of market socialism, the implication of this analysis seems clear: There is a need for the kind of government control of the allocation of investment envisaged in market socialism.