“Man once surrendering his reason, has no remaining guard against absurdities the most monstrous, and like a ship without rudder, is the sport of every wind. With such persons, gullibility, which they call faith, takes the helm from the hand of reason, and the mind becomes a wreck.”

“He who receives an idea from me, receives instruction himself without lessening mine; as he who lights his taper at mine, receives light without darkening me. That ideas should freely spread from one to another over the globe, for the moral and mutual instruction of man, and improvement of his condition, seems to have been peculiarly and benevolently designed by nature, when she made them, like fire, expansible over all space, without lessening their density in any point, and like the air in which we breathe, move, and have our physical being, incapable of confinement or exclusive appropriation.”

“I am conscious that an equal division of property is impracticable. But the consequences of this enormous inequality [in Europe] producing so much misery to the bulk of mankind, legislators cannot invent too many devices for subdividing property,...[One] means of silently lessening the inequality of property is to exempt all from taxation below a certain point, and to tax the higher portions of property in geometrical progression as they rise.”

“Do not be too severe upon the errors of the people, but reclaim them by enlightening them.”

“Leave all the afternoon for exercise and recreation, which are as necessary as reading. I will rather say more necessary because health is worth more than learning.”

“No man will ever bring out of that office the reputation which carries him into it. The honeymoon would be as short in that case as in any other, and its moments of ecstasy would be ransomed by years of torment and hatred.”

“[It is a] happy truth that man is capable of self-government, and only rendered otherwise by the moral degradation designedly superinduced on him by the wicked acts of his tyrant.”

“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.” 

“...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 have lived temperately, eating little animal food, and that not as an aliment, so much as a condiment for the vegetables, which constitute my principal diet.”

“Were I to undertake to answer the calumnies of the newspapers, it would be more than all my own time, and that of 20 aids could effect. For while I should be answering one, twenty new ones would be invented. I have thought it better to trust the justice of my country-men, that they would judge me by what they see of my conduct on the stage where they have placed me.”

“That these are our grievances which we have thus laid before his majesty, with that freedom of language and sentiment which becomes a free people claiming their rights as derived from the laws of nature, and not as the gift of their chief magistrate.”

“The only security of all is in a free press.”

“Experience declares that man is the only animal which devours his own kind; for I can apply no milder term to the governments of Europe, and to the general prey of the rich on the poor.”

“I hold it that a little rebellion now and then is a good thing, and as necessary in the political world as storms in the physical. Unsuccesful rebellions indeed generally establish the incroachments on the rights of the people which have produced them. An observation of this truth should render honest republican governors so mild in their punishment of rebellions, as not to discourage them too much. It is a medecine necessary for the sound health of government.”