"creative destruction" of capitalism—the fact that market economies undergo constant change. At any moment of time, posits Schumpeter, there are rising industries and declining industries. Schumpeter and many contemporary economists influenced by his work argue that resources should flow from the declining to the expanding industries for an economy to grow, but they recognized that sometimes resources are slow to withdraw from the declining industries because of various forms of institutional resistance to change. The Austrian economists Ludwig von Mises and Friedrich Hayek were among the leading defenders of market economy against 20th century proponents of socialist planned economies. Mises and Hayek argued that only market capitalism could manage a complex, modern economy. Among their arguments were the economic calculation problem, which was first proposed by Mises in 1920 and later expounded by Hayek. The problem referred to is that of how to distribute resources rationally in an economy. The free market solution is the price mechanism, wherein people individually have the ability to decide how a good or service should be distributed based on their willingness to give money for it. The price conveys embedded information about the abundance of resources as well as their desirability which in turn allows corrections that prevent shortages and surpluses on the basis of individual consensual decisions. Mises and Hayek argued that this is the only possible solution and without the information provided by market prices socialism lacks a method to rationally allocate resources. Mises argued in a famous 1920 article "Economic Calculation in the Socialist Commonwealth" that the pricing systems in socialist economies were necessarily deficient because if government owned or controlled the means of production, then no rational prices could be obtained for capital goods as they were merely internal transfers of goods in a socialist system and not "objects of exchange", unlike final goods, therefore they were unpriced and hence the system would be necessarily inefficient since the central planners would not know how to allocate the available resources efficiently. This led him to declare "that rational economic activity is impossible in a socialist commonwealth". Mises developed his critique of socialism more completely in his 1922 book Socialism: An Economic and Sociological Analysis. Since a modern economy produces such a large array of distinct goods and services and consists of such a large array of consumers and enterprises, asserted Mises and Hayek, the information problems facing any other form of