them; in reality they are inextricably interwoven. The economic system and the family system are in the closest relation to each other and there is a give and take between them at every point. What we call "ethical principles" and try to elevate into predominating rules for family and economic life are themselves only vague and inconclusive generalizations to which we have been led, often unconsciously, by superficial and incompetent reflection on the experiences which family and economic life, acting far above and beyond our criticism or control, have suggested to us.
So far we have seen that all the discoveries and inventions by which we find out the forces of Nature and subjugate them to our use, in effect increase the supporting power of the land, and that the standard of living, by intelligently ordering the way in which we use our added power, prevents the dispersion of it in the mere maintenance of a greater number.
It must further be noticed that all our ignorances, follies, and mistakes lessen the supporting power of the land. They do not prevent numbers from being born, but they lessen the fund on which those who are born must live, or they prevent us from winning and enjoying what the means at our disposal are really able to produce. All discord, quarreling, and war in a society have this effect. It is legitimate to think of Nature as a hard mistress against whom we are maintaining the struggle for existence. All our science and art are victories over her, but when we quarrel amongst ourselves we lose the fruits of our victory just as certainly as we should if she were a human opponent. All plunder and robbery squander the fund which has been produced by society for the support of society. It makes no difference whether the plunder and robbery are legal or illegal in form. Every violation of