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DSE學生可以不理
There is no shortage even in a society, for the simple reason that all markets must be “cleared” in order to produce equilibrium situations. If equilibrium is not attained, no theory is implied, hence economics cannot explain behaviour. If the price of a good is controlled to below the market price, the alleged presence of the shortage, hence disequilibrium, simply means that we have no theory. It is not a fact. If queuing occurs, equilibrium may again be derived as a matter of routine, but then the market is again cleared—hence no shortage.