And the social forces in equilibrium at focal points are themselves composites of many forces, cooperating and reinforcing each other, each of these forces having its own equilibria with other minor forces--a net resultant sending the unneutralized energy of both in a common direction, to form part of a bigger stream of energy. "Demand" is a stream of energy fed by many springs, among which, no doubt, individual wants for the good in question are to be found, but which include the legal and moral values of _men_, also, and an infinite host of other forces. And, just as one form of physical energy may be substituted for another, under different systems of technique, electricity taking the place of steam power, steam doing the work formerly done by horse or human power, so, in particular forms of social organization, one form of social force may do the work that is better done by some other form of social force under a different form of social organization. Thus the regulation of the details of conduct, a matter of iron law (or of custom with the force of law) in certain stages, we now leave to the control of subtler social forces. At one stage we depend on religious values, the curse and the benediction of the church, as a tremendously vital power in social control; now we find other modes of social energy frequently more efficacious. Now we depend primarily on economic social values, under a competitive system, to motivate the economic activities of society, to determine whether this piece of land shall be planted in wheat, or in some other crop, or fertilized in this or that manner; in the mediaeval English manor, many questions like these were settled by vote of the manor court. But whatever the form in which the social energy of control and motivation manifests itself, its functional character is the same. It has its origin in, and receives its vitality from, the social will--or better is a phase of the social will--as steam power, electric power, and the energy in human muscles, are species of the same generic force.