represent the strife and the defeats to which each has been subjected.

Such is the plan, such are the divisions, the order, and the spirit of the history of the four great schools of the eighteenth century which I propose to present to you. But shall I limit myself to this part of the historian? Is this impartiality, which appears like indifference, and which rests, on the contrary, upon a profound sympathy for humanity and for every thing which comes from it, the only task which I propose? No; I must propose to myself still another; and I tell you beforehand that all this tends to, and will end at, dogmatical conclusions.

There is, incontestably, a foundation of truth under the contrary errors of the four fundamental systems of philosophy, without which these very errors would be impossible. But it is the error which is diverse; the truth is one. These four systems, although different in their errors, can and must agree in the truths which they contain. The errors of the systems which destroy each other, cover truths which do not pass away, and the history of philosophy contains a true philosophy, and, as Leibnitz said, perennis philosophia, an immortal philosophy, concealed and not ruined in the eccentric developments of systems. This is the common foundation upon which we all live, people and philosophers we live in truth and by truth, thus to speak; and it is sufficient to disengage this immortal foundation from the defective and variable forms which at once obscure it and manifest it in history, in order to attain to true philosophy. I have long since* said, if philosophy does not already exist, you will search for it in vain; you will not find it. Would it not be absurd, in fact, if here, in 1829, I should pretend to show the truth, finally discovered, in this point of time and space, which had escaped three thousand years of fruitless researches, and so many generations of men of genius? The pretension is insane, and every philosophy which is thus presented is a philosophy which it is easy

* 1st Series, passim.

to confound, even before having heard the revelations which it promises. If, on the contrary, under all errors, there is in the history of philosophy as well as in the human mind, a philosophy always subsisting, always ancient and always new, it is only necessary to re-collect it. It is necessary to elevate the true side of all the systems which the history of philosophy contains, to put it in harmony with the true side of all the points of view of the human mind, to collect and offer to men that which they know already but confusedly, that which is in philosophers but in fragments, and, as it were, in shreds, that which has belonged to all time, that which will always be, but everywhere and always more or less mixed, altered, corrupted by the movement of time and human things, by the feebleness of reflection, and the systematic illusions of genius.

Such, you know, is the end of all my labors; this history of the philosophy of the eighteenth century will therefore be, properly speaking, a course of philosophy under the form of the history of philosophy, in the limits of a single epoch, an epoch which is greatest and most recent. I shall end, and wish to end, at theoretical conclusions; but these conclusions will be nothing else than the elevation and reunion of all the truths which have been put into the world, and expanded in the world by the four great schools of the eighteenth century. Every great epoch of the history of philosophy has, thus to speak, a clear result, which is composed of all the errors and all the truths which are due to this epoch: such is the legacy which it bequeathes to the epoch which follows it. The eighteenth century, also, has its clear result; it has a legacy to bequeath to the nineteenth century. I accept this legacy with gratitude, but without binding myself to discharge its obligations; I wish to clear it from dross, and present it thus to the rising generation, as its patrimony, and the foundation upon which it should work.

You comprehend the reach of the philosophical and historical enterprise which I propose to execute with you and before you. The end is good, I believe, but the route will be long; neither in

a few months, nor in a year, shall we be able to arrive at its termination. It is important, therefore, that we should take the first steps as soon as possible, and I shall take up, in the coming lecture, the first great school which offers itself to us in the eighteenth century, to wit, the sensualistic school.

LECTURE XIV.

SENSUALISTIC SCHOOL IN THE EIGHTEENTH CENTURY.

Subject of this Lecture: Review of the different systems of the sensualistic school in Europe during the eighteenth century, in England, France, and Germany.-That, even for the sake of fidelity, the historian should attach himself to the most celebrated systems.-In what order must they be studied? Ethnographical method. Three objections: 1st, arbitrary; 2d, shows not the concatenation, the reciprocal action of systems; 3d, unfavorable to scientific instruction. Of the true method of its characters: To follow at once the dates of systems, their reciprocal dependence, and the analogy of subjects.-To commence with the metaphysicians and Locke.

THE last lecture gave you the general classification of the systems which fill up the philosophy of the eighteenth century. We reduced these systems so diverse and so numerous to four schools; we determined the order in which these four schools have appeared, and consequently the order in which it is necessary to reproduce them. It is the sensualistic school which precedes the others: we will therefore examine it first.

But this school is vast; it embraces several nations and many systems! Where shall we commence ? Observe that it is not I that detains you some time yet upon this preliminary question; it is method itself, method, which checks the natural impetuosity of thought, and condemns it to undertake nothing of which it has not rendered to itself a strict account. It is the peculiarity of nascent philosophy to let itself be carried away by its object, to precipitate itself at first into every route that is offered to it; but it is the character of a more advanced philosophy to borrow from reflection the motives of all its proceedings, and to set out upon no route without having wholly measured it, without having recognized its point of departure and its issue. Thus, as we have not approached the eighteenth century at hazard, and as we

have commenced by searching out the order in which we should study the different schools of which it is composed, so we cannot approach at venture the sensualistic school; before engaging in it, it is necessary to search out also the order in which we should study the different systems which this school contains.

But we cannot classify systems of which we have not the least idea; it is, therefore, necessary to commence by a kind of recognition, by a rapid review, of all the monuments of the sensualistic school of the eighteenth century. Surely I ought not, neither do I wish to, enter into any detail, for I should anticipate the extended lectures which are to follow; I only wish to cite for you some proper names, some titles of works, and some dates; but, finally, these proper names, these titles, these dates are absolutely necessary in order that we may be able to find our way in the world where we are now taking the first steps. I am about to designate to you nearly all the phenomena which it is necessary to classify and to distribute into a convenient order.

Locke is the father of the sensualistic school of the eighteenth century; placed between the seventeenth and eighteenth centuries, he forms the transition from one to the other; he is the last term of the sensualistic school of the seventeenth century, and the first term of the sensualistic school of the eighteenth. In fact, run over all the sensualistic philosophers of the eighteenth century, there is not one who does not invoke the authority of Locke; and I do not speak merely of metaphysicians, but of moralists, publicists, and critics. Locke is the chief, the avowed master of the sensualistic school of the last century. Behold now the disciples and the representatives of this school.

In England, without speaking of Collins, Dodwell, and Mandeville, whom you know, we find, somewhat later, David Hartley, with his Observations on Man.† It is the first attempt to join

* See, in the preceding volume, the 12th Lecture, and in Vol. 3 of the 1st Serics, Lecture 2, p. 79.

† David Hartley, a physician, born in 1704, died in 1757. He published: