Dear Sir,—The copy of your Second Thoughts on Instinctive Impulses, with the letter accompanying it, was received just as I was setting out on a journey to this place, two or three days’ distant from Monticello. I brought it with me and read it with great satisfaction, and with the more as it contained exactly my own creed on the foundation of morality in man. It is really curious that on a question so fundamental, such a variety of opinions should have prevailed among men, and those, too, of the most exemplary virtue and first order of understanding. It shows how necessary was the care of the Creator in making the moral principle so much a part of our constitution as that no errors of reasoning or of speculation might lead us astray from its observance in practice. Of all the theories on this question, the most whimsical seems to have been that of Wollaston, who considers truth as the foundation of morality. The thief who steals your guinea does wrong only inasmuch as he acts a lie in using your guinea as if it were his own. Truth is certainly a branch of morality, and a very important one to society. But presented as its foundation, it is as if a tree taken up by the roots, and its stem reversed in the air, and one of its branches planted in the ground. This, too, is but a branch of our moral duties, which are generally divided into duties to God and duties to man. If we did a good act merely from the love of God and a belief that it is pleasing to Him, whence arises the morality of the Atheist? It is idle to say, as some do, that no such being exists. We have the same evidence of the fact as of most of those we act on, to-wit: their own affirmations, and their reasonings in support of them. I have observed, indeed, generally, that while in protestant countries the defections from the Platonic Christianity of the priests is to Deism, in catholic countries they are to Atheism. Diderot, D’Alembert, D’Holbach, Condorcet, are known to have been among the most virtuous of men. Their virtue, then, must have had some other foundation that the love of God.

The To xua,ov of others is founded in a different faculty, that of taste, which is not even a branch of morality. We have that of taste, which is not even a branch of morality. We have indeed an innate sense of what we call beautiful, but that is exercised chiefly on subjects addressed to the fancy, whether exercised chiefly on subjects addressed to the fancy, whether through the eye in visible forms, as landscape, animal figure, dress, drapery, architecture, the composition of colors, &c., or to the imagination directly, as imagery, style, or measure in prose or poetry, or whatever else constitutes the domain of criticism or taste, a faculty entirely distinct from the moral one. Self-interest, or rather self-love, or egoism, has been more plausibly substituted as the basis of morality. But I consider our relations with others as constituting the boundaries of morality. With ourselves we stand on the ground of identity, not of relation, with last, requiring two subjects, excludes self-love confined to a single one. To ourselves, in strict language, we can owe no duties, obligation requiring also two parties. Self-love, therefore, is no part of morality. Indeed it is exactly its counterpart. It is the sole antagonist of virtue, leading us constantly by our propensities to self-gratification in violation of our moral duties to others. Accordingly, it is against this enemy that are erected the batteries of moralists and religionists, as the only obstacle to the practice of morality. Take from man his self propensities, and he can have nothing to seduce him from the practice of virtue. Or subdue those propensities by education, instruction, or restraint, and virtue remains without a competitor. Egoism, in a broader sense, has been thus presented as the source of moral action. It has been said that we feed the hungry, clothe the naked, bind up the wounds of the man beaten by thieves, poor oil and wine into them, set him on our own beast and bring him to the inn, because we receive ourselves pleasure from these acts. So Helvetius, one of the best men on earth, and the most ingenious advocate of this principle, after defining ’interest’ to mean not merely that which is pecuniary, but what ever may procure us pleasure or withdraw us from pain, [de Pesprit 2, I] says, [ib. 2,2] “the humane m an is he to whom the sight of misfortune is insupportable, and who to rescue himself from this spectacle, is forced to succor the unfortunate object.” This indeed is true. But it is one step short of the ultimate question. These good acts give us pleasure, but how happens it that they give us pleasure? Because nature hath implanted in our breasts a love of others, a sense of duty to them, a moral instinct, in short, which prompts us irresistibly to feel and to succor their distresses, and protests against the language of Helvetius [ib. 2, 5,] “what other motive than self-interest could determine a man to generous actions? It is as impossible for him to love what is good for the sake of good, as to love evil for the sake of evil.” The Creator would indeed have been a bungling artist, had he intended man for a social animal, without planting in him social dispositions. It is true they are not planted in every man, because there is no rule without exceptions; but it is false reasoning which converts exceptions into the general rule. Some men are born without the organs of sight, or of hearing, or without hands. Yet it would be wrong to say that man is born without these faculties, and sight, hearing, and hands may with truth enter into the general definition of man. The want or imperfection of the senses of sight and hearing in others, is no proof that it is a general characteristic of the species. When it is wanting, we endeavor to supply the defect by education, by appeals to reason and calculation, by presenting to the being so unhappily conformed, other motives to do good and to eschew evil, such as the love, or the hatred, or rejection of those among whom he lives, and whose society is necessary to his happiness and even existence; demonstrations by sound calculation that honesty promotes interest in the long run; the rewards and penalties established by the laws; and ultimately the prospects of a future state of retribution for the evil as well as the good done while here. These are the correctives which are supplied by education, and which exercise the functions of the supplied by education, and which exercise the functions of the moralist, the preacher, and legislator; and they lead into a course of correct action all those whose disparity is not too profound to be eradicated. Some have argued against the existence of a moral sense, by saying that if nature had given us such a sense, impelling us to virtuous actions, and warning us against those which are vicious, then nature would also have designated, by some particular ear-marks, the two sets of actions which are, in themselves, the one virtuous and the other vicious. Whereas, we find, in fact, that the same actions are deemed virtuous in one country and vicious in another. The answer is that nature has constituted utility to man the standard and best of virtue. Men living in different countries, under different circumstances, different habits and regimens, may have different utilities; the same act, therefore, may be useful, and consequently virtuous in one country which is injurious and vicious in another differently circumstanced. I sincerely, then, believe with you in the general existence of a moral instinct. I think it is the brightest gem with which the human character is studded, and the want of it as more degrading than the most hideous of the bodily deformities. I am happy in reviewing the roll of associates in this principle which you present in your second letter, some of which I had not before met with. To these might be added Lord Kaims, one of the ablest of our advocates, who goes so far as to say, in his Principles of Natural Religion, that a man owes no duty to which he is not urged by some impulsive feeling. This is correct, if referred to the standard of general feeling in the given case, and not to the feeling of a single individual. Perhaps I may misquote him, it being fifty years since I read his book.

The leisure and solitude of my situation here has led me to the indiscretion of taking you with a long letter on a subject whereon nothing new can be offered you. I will indulge myself no farther than to repeat the assurances of my continued esteem and respect.