By examining within myself, and searching in others what could be the cause of these different manners of being, I discovered that, in a great measure they depended on the anterior impressions of external objects; and that, continually modified by our senses and organs, we, without knowing it, bore in our ideas, sentiments, and even actions, the effect of these modifications. The striking and numerous observations I had collected were beyond all manner of dispute, and by their natural principle seemed proper to furnish an exterior regimen, which varied according to circumstances, might place and support the mind in the state most favorable to virtue. From how many mistakes would reason be preserved, how many vices would be stifled in their birth, were it possible to force animal economy to favor moral order, which it so frequently disturbs! Climate, seasons, sounds, colors, light, darkness, the elements, ailments, noise, silence, motion, rest, all act on the animal machine, and consequently on the mind: all offer a thousand means, almost certain of directing in their origin the sentiments by which we suffer ourselves to be governed. Such was the fundamental idea of which I had already made a sketch upon paper, and whence I hoped for an effect the more certain, in favor of persons well disposed, who, sincerely loving virtue, were afraid of their own weakness, as it appeared to me easy to make of it a book as agreeable to read as it was to compose. I have, however, applied myself but very little to this work, the title of which was to have been ‘Morale Sensitive’ ou le Materialisme du Sage. —[Sensitive Morality, or the Materialism of the Sage.]—Interruptions, the cause of which will soon appear, prevented me from continuing it, and the fate of the sketch, which is more connected with my own than it may appear to be, will hereafter be seen.
Besides this, I had for some time meditated a system of education, of which Madam de Chenonceaux, alarmed for her son by that of her husband, had desired me to consider. The authority of friendship placed this object, although less in itself to my taste, nearer to my heart than any other. On which account this subject, of all those of which I have just spoken, is the only one I carried to its utmost extent. The end I proposed to myself in treating of it should, I think, have procured the author a better fate. But I will not here anticipate this melancholy subject. I shall have too much reason to speak of it in the course of my work.
These different objects offered me subjects of meditation for my walks; for, as I believed I had already observed, I am unable to reflect when I am not walking: the moment I stop, I think no more, and as soon as I am again in motion my head resumes its workings. I had, however, provided myself with a work for the closet upon rainy days. This was my dictionary of music, which my scattered, mutilated, and unshapen materials made it necessary to rewrite almost entirely.