We can best answer this question by considering what is implied in existence. Existence implies properties, and properties are fitnesses. Every object, by virtue of its existence, has its place, purpose, uses, relations. At every moment, each specific object is either in or out of its place, fulfilling or not fulfilling its purpose, subservient to or alienated from its uses, in accordance or out of harmony with its relations, and therefore in a state of fitness or of unfitness as regards other objects. Every object is at every moment under the control of the intelligent will either of the Supreme Being or of some finite being, and is by that will maintained either in or out of its place, purpose, uses, and relations, and thus in a state of fitness or unfitness as regards other objects. Every intelligent being, by virtue of his existence, bears certain definite relations to outward objects, his fellow-beings, and his Creator. At every moment each intelligent being is either faithful or unfaithful to these relations, and thus in a state of fitness or unfitness as regards outward objects and other beings. Thus fitness or unfitness may be predicated at every moment of every object in existence, of the volitions by which each object is controlled, and of every intelligent being with regard to his voluntary position in the universe. Fitness and unfitness are the ultimate ideas that underlie the terms _right_ and _wrong_. These last are metaphorical terms: right, _rectus_, straight, upright, according to rule, and therefore _fit_; wrong, _wrung_, distorted, twisted out of place, abnormal, and therefore _unfit_. We are so constituted that we cannot help regarding fitness with esteem and complacency; unfitness, with disesteem and disapproval, even though we ourselves create it or impersonate it. Fitness is the law by which alone we have the knowledge of sin, by which alone we justify or condemn ourselves. Duty has fitness for its only aim and end. To whatever object comes under our control its fit place or use is due; and our perception of that _due_ constitutes our _duty_, and awakens in us a sense of obligation. To ourselves and to other beings and objects, our fidelity to our relations has in it an intrinsic fitness; that fitness is their and our due; and the perception of that _due_ constitutes our _duty_, and awakens in us a sense of obligation.