John Spargo, Socialism: A Summary and Interpretation of Socialist Principles
“ Stated in the simple, crude form, that the quantity of human labor crystallized in them is the basis and measure of the value of commodities when exchanged against one another, the labor theory of value is beautifully simple. At least, the formula is simplicity itself. At the same time, it is open to certain very obvious criticisms. It would be absurd to contend that the day's labor of a coolie laborer is equal in productivity to the day's labor of a highly skilled mechanic, or that the day's labor of an incompetent workman is of equal value to that of the most proficient. ”
