ABSTRACT
It cannot be repeated too often that the case of perfect competition owes the fundamental importance which it always had and still has in economic theory to certain properties characteristic of it and neither to any tendency in the facts to conform to it nor any 'desirability' of the state of things it depicts. For any science or part of a science, the first task always consists in establishing the logical autonomy of its field, or rather the conditions under which there is logical autonomy. It is nevertheless but fair to state that we owe substantial progress to the works of all the theorists of imperfect competition, among whom Mrs. Robinson establishes a claim, certainly to a leading, and perhaps to the first, place. Mrs. Robinson says that her fundamental assumption is 'that each individual acts in a sensible manner in the circumstances in which he finds himself from the point of view of his own economic interests'.
