People engage in exchange to attain goals. Exchange is not just take; in order to get, one must give. People must do things that they do not want to do in order to get things that they desire. The unpleasant part of this process is work and production, and the pleasant part is consumption. Economists assume that work and production are not pursued for their own sakes, but only because without them we cannot consume. This division of economic life is illustrated below in what Frank Knight called the Wheel of Wealth, but which is now commonly known as circular flow.