Your undertaking the twelve volumes of Dupuis, is a degree of heroism to which I could not have aspired even in my younger days. I have been contented with the humble achievement of reading the analysis of his work by Destutt Tracy, in two hundred pages octavo. I believe I should have ventured on his own abridgment of the work, in one octavo volume, had it ever come to my hands; but the marrow of it in Tracy has satisfied my appetite; and even in that, the preliminary discourse of the analyzer himself, and his conclusion, are worth more in my eye than the body of the work. For the object of that seems to be to smother all history under the mantle of allegory. If histories so unlike as those of Hercules and Jesus, can, by a fertile imagination and allegorical interpretations, be brought to the same tally, no line of distinction remains between fact and fancy. As this pithy morsel will not overburthen the mail in passing and repassing between Quincy and Monticello, I send it for your perusal. Perhaps it will satisfy you, as it has me; and may save you the labor of reading twenty-four times its volume. I have said to you that it was written by Tracy; and I had so entered it on the title page, as I usually do on anonymous works whose authors are known to me. But Tracy requested me not to betray his anonyme, for reasons which may not yet, perhaps, have ceased to weigh. I am bound, then, to make the same reserve with you. Destutt Tracy is, in my judgment, the ablest writer living on intellectual subjects, or the operations of the understanding. His three octavo volumes on Ideology, which constitute the foundation of what he has since written, I have not entirely read; because I am not fond of reading what is merely abstract, and unapplied immediately to some useful science. Bonaparte, with his repeated derisions of Ideologists (squinting at this author), has by this time felt that true wisdom does not lie in mere practice without principle. The next work Tracy wrote was the Commentary on Montesquieu, never published in the original, because not safe; but translated and published in Philadelphia, yet without the author's name. He has since permitted his name to be mentioned. Although called a Commentary, it is, in truth, an elementary work on the principles of government, comprised in about three hundred pages octavo. He has lately published a third work, on Political Economy, comprising the whole subject within about the same compass; in which all its principles are demonstrated with the severity of Euclid, and, like him, without ever using a superfluous word. I have procured this to be translated, and have been four years endeavoring to get it printed; but as yet, without success. In the meantime, the author has published the original in France, which he thought unsafe while Bonaparte was in power. No printed copy, I believe, has yet reached this country. He has his fourth and last work now in the press at Paris, closing, as he conceives,