All of the preceding discussion of the division of labor can be summarized by saying that the division of labor increases the efficiency with which man is able to apply his mind, his body, and his nature-given environment to production. It expands his capacity to store and use knowledge, which knowledge it raises to a standard set by the most intelligent members of society. This standard in turn tends to rise higher and higher in each succeeding generation, as creative geniuses again and again enlarge the stock of technological knowledge. The division of labor also increases the degree to which knowledge of production is assimilated, the yield to the time spent in acquiring it, and the efficiency with which it is disseminated.

It increases the efficiency with which man applies his body to production inasmuch as it enables everyone to concentrate on whatever he is relatively best suited for by virtue of his bodily endowment. It also eliminates unnecessary motion in production. And, finally, it makes possible the addition of machine and mechanical power to the power of human muscles. This last enables man to accomplish physical results that would otherwise be unthinkable.

Similarly, by means of geographical specialization the division of labor increases the efficiency with which man applies his nature-given environment to production. And it does so even more by the use of ever improved machinery and methods of production that flow from the heightened and progressively increasing efficiency that it lends to man's use of his mind and body. This enables man to obtain progressively more from his environment.

On the basis of all of the foregoing considerations, it should be obvious that from the perspective of the production of wealth and all that depends on the production of wealth, a division-of-labor society is the form of society that is appropriate to man's nature. While man always possesses the faculty of reason, a division-oflabor society is necessary if he is to use his rationality efficiently in production. It is necessary if he is to actualize the productive potential provided by his possession of reason.

It should be equally obvious that the existence of a division-of-labor society is to the material self-interest of every individual. Whoever, in the words of von Mises, prefers wealth to poverty and life and health to sickness and death, is logically obliged to value the existence of a division-of-labor society and all that it depends on. For it is the essential foundation of all significant wealth and of the vital contribution made by wealth to man's life and health. Take away a division-of-labor society, and production shrivels to the level of medieval feudalism, with its consequently recurring famines and plagues and resulting average life expectancy of twenty-five years-years, it should never be forgotten, whose passage was marked with cold, hunger, exhaustion, and pain. Apart from the amelioration provided by Western aid in the form of food and medicines, such continues to be the miserable condition of human life today in all that vast part of the world that is not integrated into the division of labor.

Thus, the widely held notion that life in society requires the sacrifice of the individual's self-interest is totally mistaken in regard to a division-of-labor society. That notion applies only to societies characterized by force and plunder, not to a division-of-labor society. A division-of-labor society represents the mutual cooperation of individuals for the purpose of achieving their own individual ends. The radical and progressive increase in the productivity of labor it brings about makes it possible for everyone to achieve his ends incalculably better within its framework than outside of it.