virtue of their special capacities, are alone capable of the effort requisite to perform this feat; and it matters nothing to others, by whom the efreets' services are borrowed, whether the effort in question occupied a year or a day, or whether it took place yesterday or fifty years ago. The borrowed efreet produces the same surplus in either case, and interest is a part of this surplus which goes, not to the efreet himself (for this is not possible), but to his master, just as a cab-fare is paid to the cabman and not his horse. Machine-capital, then--or capital in its typical modern form--consists of productive forces which are usable by, and which indeed exist for, the human race at large, because, and only because, they have been captured and imprisoned in implements by the efforts of exceptional men, whose energy thus exercised is perpetuated, and can be lent to others; and what these men receive as interest from those by whom their energy is borrowed, is a something ultimately due to the energy of the lenders themselves--nor is this fact in any way altered by lapse of time. Thus, so far as these special men are concerned, the alleged difference between earned income and unearned altogether disappears; and if one man lives in luxury for sixty years on the interest of an invention which it took him but a month to perfect, while another man every day has to toil for his daily bread, the difference between the two consists not in the fact that the one man works for his bread and the other man does nothing for it, but in the fact that the work of one produces more in a day than that of the other would do in a hundred lifetimes. Here, however, we shall be met with two important objections. In the first place, it will no doubt have occurred to many readers that throughout the foregoing discussion we have assumed that the persons who receive interest on machinery are in all cases the persons by whom the machinery was invented and produced. To the actual inventors and producers it may, indeed, be conceded that the interest which they themselves receive has been earned by their own exertions; but no such concession, it will be said, can be made to these men's heirs. An Edison or a Bessemer may have produced whatever income has come to him in his latest years from the inventive efforts of his earliest; but if such a man has a son to whom this income descends--a half-witted degenerate who squanders it on wine and women, who will not work with his hands and who cannot work with his head--no one can pretend that, in any sense of the word, a fool like this produces any fraction of the thousands that he consumes. And though all of those who live on the interest of inherited capital are not foolish nor vicious, yet in this respect they are all of them in the same position--they have not produced their incomes, and so have no moral right to them.