Throughout the present discussion we have been assuming that the questions at issue turn ultimately on the character of human motive.  On both sides it has been assumed that men of exceptional powers will not produce exceptional amounts of wealth, unless they are allowed the right of enjoying some substantial proportion of it.  This is a psychological truth which, together with its social consequences, has been dealt with elaborately in two of our earlier chapters.  It was there shown that the production of exceptional wealth by those men whose peculiar powers alone enable them to produce it, involves efforts on their part which, unlike labour, cannot be exacted of them by any outside compulsion, but can only be educed by the prospect of a secured reward; and that this reward consists, as has just been said, of the enjoyment of a part of the product proportionate to the magnitude of the whole.  But what the proportion should be, and in what manner it should be enjoyed, were questions which were then passed over.  They were passed over in order that they might be discussed separately.  It was pointed out, however, that the reward, in order to be operative, must be such as will be felt to be sufficient by these men themselves, and that its precise amount and quality can be determined by them alone—­just as, if what we desire is to coax an invalid to eat, we can coax him only with food which he himself finds appetising.  Let us now take these questions up again, and examine them more minutely, and we shall find that interest is justified from a practical point of view by the fact that the enjoyment of capital by this particular means is not only the sole manner of enjoying it which is consistent with the general welfare, but also constitutes the advantage which, in the eyes of most great producers, gives to capital the larger part of its value, and renders the desire of producing it efficient as a social motive.

The reasons why the right to interest forms, in the eyes of the active producers of capital, the main object of their activity are to be found, firstly, in the facts of family affection, and, secondarily, in those of general social intercourse, which together form the medium of by far the larger part of our satisfactions.  In spite of the selfishness which distinguishes so much of human action, a man’s desire to secure for his family such wealth as he can is one of the strongest motives of human activity known; and the fact that it operates in the case of many who are notoriously selfish otherwise, shows how deeply it is ingrained in the human character.  One of the first uses to which a man who has produced great wealth puts it is in most cases to build a house more or less proportionate to his means; and it is his pride and pleasure to see his wife and children acclimatise themselves to their new environment.  But such a house would lose most of its charm and meaning for him if the fortune which enabled him to live in it were to dwindle with each day’s expenditure,