“I felt enough of the effect of withdrawing from the world then, to see that it led to an antisocial and misanthropic state of mind, which severely punished him who gives in to it. And it will be a lesson I never shall forget as to myself.”

“Whenever the people are well-informed, they can be trusted with their own government”

“The object most interesting to me for the residue of my life, will be to see you both developing daily those principles of virtue and goodness which will make you valuable to others and happy in yourselves, and acquiring those talents and that degree of science which will guard you at all times against ennui, the most dangerous poison of life. A mind always employed is always happy. This is the true secret, the grand recipe for felicity....In a world which furnishes so many employments which are useful, and so many which are amusing, it is our own fault if we ever know what ennui is...”

“Speaking one day to Monsieur de Buffon, on the present ardor of chemical inquiry, he affected to consider chemistry but as cookery, and to place the toils of the laboratory on the footing with those of the kitchen. I think it, on the contrary, among the most useful of sciences, and big with future discoveries for the utility and safety of the human race.”

“I shall not die without a hope that light and liberty are on a steady advance. Even should the cloud of barbarism and despotism again obscure the science and liberties of Europe, this country remains to preserve and restore light and liberty to them. In, short, the flames kindled on the 4th of July, 1776, have spread over too much of the globe to be extinguished by the feeble engines of despotism; on the contrary, they will consume these and all who work for them.”

“The vote being passed, altho' further observn on it was out of order, he could not refrain from rising and expressing his satisfaction and concluded by saying "there is but one word, Mr. President, in the paper which I disapprove, & that is the word Congress," on which Ben Harrison rose and said "there is but on word in the paper, Mr. President, of which I approve, and that is the word Congress.”

“Sometimes it is said that man cannot be trusted with the government of himself. Can he, then, be trusted with the government of others? Or have we found angels in the form of kings to govern him? Let history answer this question.”

“[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.”

“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.”

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

“Timid men prefer the calm of despotism to the tempestuous sea of Liberty.”

“The earth belongs always to the living generations.”

“To your request of my opinion of the manner in which a newspaper should be conducted, so as to be most useful, I should answer, ‘by restraining it to true facts & sound principles only.’ Yet I fear such a paper would find few subscribers. It is a melancholy truth, that a suppression of the press could not more compleatly deprive the nation of its benefits, than is done by its abandoned prostitution to falsehood. Nothing can now be believed which is seen in a newspaper. Truth itself becomes suspicious by being put into that polluted vehicle. The real extent of this state of misinformation is known only to those who are in situations to confront facts within their knolege with the lies of the day. I really look with commiseration over the great body of my fellow citizens, who, reading newspapers, live & die in the belief, that they have known something of what has been passing in the world in their time; whereas the accounts they have read in newspapers are just as true a history of any other period of the world as of the present, except that the real names of the day are affixed to their fables. General facts may indeed be collected from them, such as that Europe is now at war, that Bonaparte has been a successful warrior, that he has subjected a great portion of Europe to his will, &c., &c.; but no details can be relied on. I will add, that the man who never looks into a newspaper is better informed than he who reads them; inasmuch as he who knows nothing is nearer to truth than he whose mind is filled with falsehoods & errors. He who reads nothing will still learn the great facts, and the details are all false.” —Letter to John Norvell, 14 June 1807 [Works 10:417--18]” 

“To compel a man to subsidize with his taxes the propagation of ideas which he disbelieves and abhors is sinful and tyrannical.”

“I predict future happiness for Americans, if they can prevent the government from wasting the labors of the people under the pretense of taking care of them.”