“It is incumbent on every generation to pay its own debts as it goes. A principle which if acted on would save one-half the wars of the world.”

“To compel a man to furnish funds for the propagation of ideas he disbelieves and abhors is sinful and tyrannical.”

“Neither Pagan nor Mahamedan nor Jew ought to be excluded from the civil rights of the Commonwealth because of his religion. -quoting John Locke's argument.”

“If by religion we are to understand sectarian dogmas, in which no two of them agree, then your exclamation on that hypothesis is just, "that this would be the best of worlds if there were no religion in it.” 

“A nation which expects to be ignorant and free, in a state of civilization, expects that which never was and never will be.”

“Here was buried Thomas Jefferson, author of the Declaration of American Independence, of the Statute of Virginia for Religious Freedom, and Father of the University of Virginia.

“...We are all Federalists,and we are all Republicans.”

“… 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 and errors.”

“Some men look at constitutions with sanctimonious reverence, and deem them like the ark of the covenant, too sacred to be touched. They ascribe to the men of the preceding age a wisdom more than human, and suppose what they did to be beyond amendment. I knew that age well; I belonged to it, and labored with it. It deserved well of its country. It was very like the present, but without the experience of the present; and forty years of experience in government is worth a century of book-reading; and this they would say themselves, were they to rise from the dead. I am certainly not an advocate for frequent and untried changes in laws and constitutions. I think moderate imperfections had better be borne with; because, when once known, we accommodate ourselves to them, and find practical means of correcting their ill effects. But I know also, that laws and institutions must go hand in hand with the progress of the human mind. As that becomes more developed, more enlightened, as new discoveries are made, new truths disclosed, and manners and opinions change with the change of circumstances, institutions must advance also, and keep pace with the times. We might as well require a man to wear still the coat which fitted him when a boy, as civilized society to remain ever under the regimen of their barbarous ancestors.” 

“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]” 

“We believe no more in Bonaparte's fighting merely for the liberties of the seas than in Great Britain's fighting for the liberties of mankind. The object is the same, to draw to themselves the power, the wealth and the resources of other nations.”

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

“The doctor of the future will give no medicine, but will interest his (sic)patient in the care of the human frame, in diet and in the cause and prevention of disease”

“Truth is great and will prevail if left to herself, that she is the proper and sufficient antagonist to error, and has nothing to fear from the conflict, unless by human interposition disarmed of her natural weapons, free argument and debate; errors ceasing to be dangerous when it is permitted freely to contradict them.”

“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.”