ABSTRACT
§ 1. The rate of return per unit in money obtained from any quantity of any kind of productive resource in any use is, in general, equal to the value of the marginal private net product of that quantity of that kind of resource there. As between different occupations and places, therefore, the relation between rates of return is the same as the relation between values of marginal private net products; so that equality or inequality among rates of return is the same thing as equality or inequality among values of marginal private net products. In this and the four following chapters I shall, for convenience, sometimes use the term of rate of returns—or, more loosely, returns—in place of the longer synonym.
