“I am not a Federalist because I never submitted the whole system of my opinions to the creed of any party of men whatever....Such an addiction is the last degradation of a free and moral agent. If I could not go to heaven but with a party, I would not go there at all.”

“...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.”

“I set out on this ground, which I suppose to be self-evident, that the earth belongs in usufruct to the living.”

“Our Revolution commenced on more favorable ground. It presented us an album on which we were free to write what we pleased. We had no occasion to search into musty records, to hunt up royal parchments, or to investigate the laws and institutions of a semi-barbarous ancestry. We appealed to those of nature, and found them engraved on our hearts. Yet we did not avail ourselves of all the advantages of our position. We had never been permitted to exercise self-government. When forced to assume it, we were novices in its science. Its principles and forms had entered little into our former education. We established however some, although not all its important principles. The constitutions of most of our States assert, that all power is inherent in the people; that they may exercise it by themselves, in all cases to which they think themselves competent, (as in electing their functionaries executive and legislative, and deciding by a jury of themselves, in all judiciary cases in which any fact is involved,) or they may act by representatives, freely and equally chosen; that it is their right and duty to be at all times armed; that they are entitled to freedom of person, freedom of religion, freedom of property, and freedom of the press.”

“You have heard of the new chemical nomenclature endeavored to be introduced by Lavoisier, Fourcroy, &c. Other chemists of this country, of equal note, reject it, and prove in my opinion that it is premature, insufficient and false. These latter are joined by the British chemists; and upon the whole, I think the new nomenclature will be rejected, after doing more harm than good. There are some good publications in it, which must be translated into the ordinary chemical language before they will be useful.”

“When the people fear the government there is tyranny, when the government fears the people there is liberty.”

“I had rather be shut up in a very modest cottage with my books, my family and a few old friends, dining on simple bacon, and letting the world roll on as it liked, than to occupy the most splendid post, which any human power can give.”

“The main objects of all science, the freedom and happiness of man. . . . [are] the sole objects of all legitimate government.

“The whole commerce between master and slave is a perpetual exercise of the most boisterous passions, the most unremitting despotism on the one part, and degrading subjugation on the other. Our children see this, and learn to imitate it: for man is an imitative animal.”

“The legitimate powers of government extend to such acts only as are injurious to others. It does me no injury for my neighbor to say there are twenty gods or no god. It neither picks my pocket nor breaks my leg.”

“Later, he told his nephew that religion required careful thought, not reflexive acceptance. "Fix reason firmly in her seat, and call to her tribunal every fact, every opinion. Question with boldness even the existence of a God; because, if there be one, he must more approve the homage of reason, than that of blindfolded fear”

“Those who expect to be both ignorant and free, expect what never was and never will be.” 

“I hope that we shall crush in its birth the aristocracy of our monied corporations which dare already to challenge our government to a trial of strength, and bid defiance to the laws of our country.”

“Whenever you do a thing, act as if all the world were watching.”

“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”