Capitalist society is characterized by a degree of labor mobility much greater than prevailed in any previous form of society. - Paul Sweezy

Discussions of methodology in economics, as in other fields, are likely to be tiresome and unrewarding. Nevertheless, to avoid the problem altogether is to risk serious misunderstanding.

So far as the individual capitalists are concerned, each takes the wage level for granted and attempts to do the best he can for himself. In introducing machinery he is therefore merely attempting to economize on his own wage bill. The net effect of all the capitalists’ behaving in this way, however, is to create unemployment which in turn acts upon the wage level itself. It follows that the stronger the tendency of wages to rise, the stronger also will be the counteracting pressure of the reserve army, and vice versa.

In possessing use value a commodity is in no way peculiar. Objects of human consumption in every age and in every form of society likewise possess use value. Use value is an expression of a certain relation between the consumer and the object consumed. Political economy, on the other hand, is a social science of the relations between people.