appearance of a Hobbes, of a Hume, or of a Shaftesbury, is important in their time, so the appearance of a Bentham or of a Spencer out of their time is insignificant, for these latter amuse themselves with the useful, with association and evolution (which according to them should become the socially useful), and with the double principle of egoism and of altruism. Stuart Mill alone can afford some interest, when he says (with that mental inconclusiveness which has seemed to many to be acuteness and equilibrium) that moral pleasures differ from the sensual, not only in degree, but also in genus and in quality (_in kind_); and that justice is a class of socially useful actions that arouses feelings themselves also different, not only in degree, but also in genus and in quality (_in kind_), from those caused by useful actions. In short, the philosophy of the nineteenth century has not only been unable to progress, but has not even been able to maintain itself on a level with the practical doctrines of Fichte and of Hegel, in which a glimpse was caught of the relation of first and second practical degree, and there was a tendency to reconcile passion and ethicity. [Sidenote: _Extrinsic union of Ethic and of economic Science, from antiquity to the nineteenth century._] VI. Certainly economic science, owing to its empirico-quantitative character, already noted, was not made to fill the void and to furnish a more positive and exact concept of the useful. The contact between Economy and Philosophy remained for a time extrinsic, since economic Science appeared in treatises upon the Philosophy of the practical, together with the other juridical and historical matter, which it was customary to include with it. The precedent for such a union could be found even in Aristotle's _Nichomachean Ethic,_ which supplies certain notions as to the concept of price and value. Considerations on the same argument abound in the Scholastics, especially in St. Thomas, whose _Oeconomica_ always forms part of his Ethic, as the doctrine for the government of the family. Finally, there is an ample discussion of the subject in the treatises of the seventeenth and eighteenth centuries, which took the name of _natural Rights._ It happened that the English moralists of the eighteenth century were also led to occupy themselves with Economy and the economists with Ethic, owing to the juxtaposition of the two concepts for didascalic reasons and for University convenience. Thus Hutcheson developed Economy, in his _Short Introduction to Moral Philosophy_ (1747); and the _Essays_ of Hume are occupied with moral and economic questions; and Adam Smith is the author, not only of _The Wealth of Nations,_ but also of _The Theory of the Moral Feelings,_ almost two parts of a Philosophy of the practical. The importance of economic studies had become so palpable at that time, that toward the end of the century, Buhle was led to include