Evidently the acceptance of these immutable premises, tacitly, because uncritically and as a matter of course, by hedonistic economics gives the science a distinctive character and places it in contrast with other sciences whose premises are of a different order. As has already been indicated, the premises in question, so far as they are peculiar to the hedonistic economics, are (_a_) a certain institutional situation, the substantial feature of which is the natural right of ownership, and (_b_) the hedonistic calculus. The distinctive character given to this system of theory by these postulates and by the point of view resulting from their acceptance may be summed up broadly and concisely in saying that the theory is confined to the ground of sufficient reason instead of proceeding on the ground of efficient cause. The contrary is true of modern science, generally (except mathematics), particularly of such sciences as have to do with the phenomena of life and growth. The difference may seem trivial. It is serious only in its consequences. The two methods of inference--from sufficient reason and from efficient cause--are out of touch with one another and there is no transition from one to the other: no method of converting the procedure or the results of the one into those of the other. The immediate consequence is that the resulting economic theory is of a teleological character--"deductive" or "a priori" as it is often called--instead of being drawn in terms of cause and effect. The relation sought by this theory among the facts with which it is occupied is the control exercised by future (apprehended) events over present conduct. Current phenomena are dealt with as conditioned by their future consequences; and in strict marginal-utility theory they can be dealt with only in respect of their control of the present by consideration of the future. Such a (logical) relation of control or guidance between the future and the present of course involves an exercise of intelligence, a taking thought, and hence an intelligent agent through whose discriminating forethought the apprehended future may affect the current course of events; unless, indeed, one were to admit something in the way of a providential order of nature or some occult line of stress of the nature of sympathetic magic. Barring magical and providential elements, the relation of sufficient reason runs by way of the interested discrimination, the forethought, of an agent who takes thought of the future and guides his present activity by regard for this future. The relation of sufficient reason runs only from the (apprehended) future into the present, and it is solely of an intellectual, subjective, personal, teleological character and force; while the relation of cause and effect runs only in the contrary direction, and it is solely of an objective, impersonal, materialistic character and force. The modern scheme of knowledge, on the whole, rests, for its definitive ground, on