Abstract
Capitalism has many characteristics different from the former economic system, and usually the first characteristic should be commodity economy. It is because every wealth appear as commodities in capitalism. However, why does capitalism have this characteristic? In our opinion, it is because machineries introduced merit of specialization to our society and it led social division of labor. In this sense, its base is 'technology'. Every basic social change was introduced by the technological change. One more point that should be discussed on this characteristic is that social division of labor needs money for its exchange. It can be shown by comparing two situations that is with money and without money. However, social division of labor with money is not always better than without money. It needs some conditions on the number of producers and number of products. This paper explains these special conditions by a mathematical modeling. Generally, it shows that simple small community did not need any money, while large complicated society needs money for exchange. In this sense, we can understand that money is a historical product which we human beings invented in a certain historical stage.
