If we consider how rational control may be achieved we are led at once into the question of standards of service. If we could devise and apply, in connection with every function, some sound test of performance, so that all concerned might know just what good service is, and how the service of one agent compares with that of another, the question of control would become simple. This would not only act directly to promote efficiency of every sort through selecting the best men and methods, and holding them to a high grade of work, but would have an immeasurably beneficent effect in diffusing through the community order, contentment, clearness of purpose, and good-will, instead of the confusion, unrest, and hostility that now so largely prevail. Standards of any kind, if generally accepted, have the same kind of effect that the use of money has in economic exchanges: they make relations definite and thus facilitate co-operation and allay disputes. Ill-feeling, whether toward other persons or toward life in general, is based chiefly, perhaps, on resentments and perplexities arising from the lack of settled valuations. If we all knew what our place in life was and what our just claims were, as compared with those of others, the confusion that now prevails would subside. We may distinguish, as regards human conduct, two sorts of standards: the higher or emulative, instigating us to attain or approach an ideal, and minimum standards or limits of toleration, conformity to which is more or less compulsory. The former appeal to the more capable and ambitious, the latter are imposed on the backward. One defines the type at the bottom, the other at the top. In almost every kind of activity it is harmful to tolerate those who fall below a certain level of achievement: they not only set a bad example and lower the grade of service, but impair co-operation and _esprit de corps_. Even in competitive games, such as foot-racing, jumping, golf, and the like, it is usual to classify the players so that those in each group shall be sufficiently homogeneous to incite one another to do their best; and every one knows how detrimental is the influence of a player of a lower class. In the breeding of animals we have the immemorial practice of eliminating individuals who lack certain “points,” and the social science of eugenics aims, in a similar manner, to set a standard of propagation for the human race. Our whole body of penal law is a system of minimum requirements as to conduct, and the conventions or _mores_ enforced by public sentiment have much the same character.