Alfred Marshall began the second of two chapters on the subject of profits and business power with the apologetic comment that “The causes that govern Earnings of Management have not been studied with any great care till within the last fifty years”. He had just completed his argument that, in the case of Joint-stock companies, “… most of the work of management is divided between salaried directors… and salaried managers and other subordinate officials, most of whom have little or no capital af any kind; and their earnings, being almost the pure earnings of labor, are governed in the long run by those general causes which rule the earnings of labor of equal difficulty and disagreeableness in ordinary occupations”. Furthermore, he suggested that, “The supply of business power is large and elastic, since the area from which it is drawn is wide. Everyone has the business of his own life to conduct; and in this he can gain some training for business management, if he has the natural aptitudes for it.