Common sense is deposited in its works. All languages, and all human institutions contain the ideas and the sentiments that we have just called to mind and described, and especially the distinction between good and evil, between justice and injustice, between free will and desire, between duty and interest, between virtue and happiness, with the profoundly rooted belief that happiness is a recompense due to virtue, and that crime in itself deserves to be punished, and calls for the reparation of a just suffering. These things are attested by the words and actions of men. Such are the sincere and impartial, but somewhat confused, somewhat gross notions of common sense. Here begins the part of philosophy. It has before it two different routes; it can do one of two things: either accept the notions of common sense, elucidate them, thereby develop and increase them, and, by faithfully expressing them, fortify the natural beliefs of humanity; or, preoccupied with such or such a principle, impose it upon the natural data of common sense, admit those that agree with this principle, artificially bend the others to these, or openly deny them; this is what is called making a system. Philosophic systems are not philosophy; they try to realize the idea of it, as civil institutions try to realize that of justice, as the arts express in their way infinite beauty, as the sciences pursue universal science. Philosophic systems are necessarily very imperfect, otherwise there never would have been two systems in the world. Fortunate are those that go on doing good, that expand in the minds and souls of men, with some innocent errors, the sacred love of the true, the beautiful, and the good! But philosophic systems follow their times much more than they direct them; they receive their spirit from the hands of their age. Transferred to France towards the close of the regency and under the reign of Louis XV., the philosophy of Locke gave birth there to a celebrated school, which for a long time governed and still subsists among us, protected by ancient habits, but in radical opposition to our new institutions and our new wants. Sprung from the bosom of tempests, nourished in the cradle of a revolution, brought up under the bad discipline of the genius of war, the nineteenth century cannot recognize its image and find its instincts in a philosophy born under the influence of the voluptuous refinements of Versailles, admirably fitted for the decrepitude of an arbitrary monarchy, but not for the laborious life of a young liberty surrounded with perils. As for us, after having combated the philosophy of sensation in the metaphysics which it substituted for Cartesianism, and in the deplorable aesthetics, now too accredited, under which succumbed our great national art of the seventeenth century, we do not hesitate to combat it again in the ethics that were its necessary product, the ethics of interest.