Empiricism is, therefore, convicted of being unable to dispense with universal and necessary principles, and of being unable to explain them. Let us pause: either all our preceding works have terminated in nothing but chimeras, or they permit us to consider as a point definitely acquired for science, that there are in the human mind, for whomsoever interrogates it sincerely, principles really stamped with the character of universality and necessity. After having established and defended the existence of universal and necessary principles, we might investigate and pursue this kind of principles in all the departments of human knowledge, and attempt an exact and rigorous classification; but illustrious examples have taught us to fear to compromise truths of the greatest price by mixing with them conjectures which, in giving brilliancy, perhaps, to the spirit of philosophy, diminish its authority in the eyes of the wise. We, also, following the example of Kant, attempted before you, last year,[21] a classification, even a reduction of universal and necessary principles, and of all the notions that are connected with them. This work has not lost for us its importance, but we will not reproduce it. In the interest of the great cause which we serve, and taking thought here only to establish upon solid foundations the doctrine which is adapted to the French genius in the nineteenth century, we will carefully shun every thing that might seem personal and hazardous; and, instead of examining, criticising,[22] and reconstituting the classification which the philosophy of Koenigsberg has given of universal and necessary principles, we prefer, we find it much more useful, to enable you to penetrate deeper into the nature of these principles, by showing you what faculty of ours it is that discovers them to us, and to which they are related and correspond. The peculiarity of these principles is, that each one of us in reflection recognizes that he possesses them, but that he is not their author. We conceive them and apply them, we do not constitute them. Let us interrogate our consciousness. Do we refer to ourselves, for example, the definitions of geometry, as we do certain movements of which we feel ourselves to be the cause? If it is I who make these definitions, they are therefore mine, I can unmake them, modify them, change them, even annihilate them. It is certain that I cannot do it. I am not, then, the author of them. It has also been demonstrated that the principles of which we have spoken cannot be derived from sensation, which is variable, limited, incapable of producing and authorizing any thing universal and necessary. I arrive, then, at the following consequence, also necessary:--truth is in me and not by me. As sensibility puts me in relation with the physical world, so another faculty puts me in communication with the truths that depend upon neither the world nor me, and that faculty is reason.