“He has endeavoured to prevent the population of these States; for that purpose obstructing the Laws of Naturalization of Foreigners; refusing to pass others to encourage their migration hither, and raising the conditions of new Appropriations of Lands.”

“So inscrutable is the arrangement of causes and consequences in this world, that a two-penny duty on tea, unjustly imposed in a sequestered part of it, changes the condition of all its inhabitants.”

“Without books, I would certainly die.”

“I am savage enough to prefer the woods, the wilds, and the independence of Monticello, to all the brilliant pleasures of this gay capital [Paris].”

“when you come to the end of your rope, tie a knot and hang on”

“While the art of printing is left to us science can never be retrograde; what is once acquired of real knowledge can never be lost.”

“In a republican nation, whose citizens are to be led by reason and persuasion and not by force, the art of reasoning becomes of first importance”

“The glow of one warm thought is to me worth more than money.”

“He who knows best knows how little he knows.”

“I never considered a difference of opinion in politics, in religion, in philosophy, as cause for withdrawing from a friend.” 

“The object of walking is to relax the mind. You should therefore not permit yourself even to think while you walk. But divert your attention by the objects surrounding you.”

“It is neither wealth nor splendor, but tranquility and occupation which give happiness.”

“The most valuable of all talents is that of never using two words when one will do.”

“...never [enter] into dispute or argument with another. I never saw an instance of one of two disputants convincing the other by argument. I have seen many, on their getting warm, becoming rude, & shooting one another. ... When I hear another express an opinion which is not mine, I say to myself, he has a right to his opinion, as I to mine; why should I question it? His error does me no injury, and shall I become a Don Quixote, to bring all men by force of argument to one opinion? ... There are two classes of disputants most frequently to be met with among us. The first is of young students, just entered the threshold of science, with a first view of its outlines, not yet filled up with the details & modifications which a further progress would bring to their knoledge. The other consists of the ill-tempered & rude men in society, who have taken up a passion for politics. ... Consider yourself, when with them, as among the patients of Bedlam, needing medical more than moral counsel. Be a listener only, keep within yourself, and endeavor to establish with yourself the habit of silence, especially on politics. In the fevered state of our country, no good can ever result from any attempt to set one of these fiery zealots to rights, either in fact or principle. They are determined as to the facts they will believe, and the opinions on which they will act. Get by them, therefore, as you would by an angry bull; it is not for a man of sense to dispute the road with such an animal.”

“The attempt of Lavoisier to reform chemical nomenclature is premature. One single experiment may destroy the whole filiation of his terms; and his string of sulphates, sulphites, and sulphures, may have served no end than to have retarded the progress of science by a jargon, from the confusion of which time will be requisite to extricate us.”