The basis of a correct theory of obligation lies, as already stated, in holding fast to its concrete relations to the moral end, or good. This end consists in an activity in which capacity is exercised in accordance with surroundings, with the social needs which affect the individual. It is implied in this very idea, that the end is not something which the individual may set up at his own arbitrary will. The social needs give control, law, authority. The individual may not manifest his capacity, satisfy his desires, apart from their specific relation to the environment in which they exist. The general fact of obligation which is constituted through this control of capacity by the wider function is, of course, differentiated into specific 'laws' or duties by the various forms which the one function takes, as capacity and circumstances vary. In other words, obligation or duty is simply the aspect which the good or the moral end assumes, as the individual conceives of it. From the very fact that the end is the good, and yet is not realized by the individual, it presents itself to him as that which _should be realized_--as the ideal of action. It requires no further argument to show that obligation is at once self-imposed, and social in its content. It is self-imposed because it flows from the good, from the idea of the full activity of the individual's own will. It is no law imposed from without; but is his own law, the law of his own function, of his individuality. Its social content flows from the fact that this individuality is not mere capacity, but is this capacity _acting_, and acting so as to comprehend social relationships.