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

“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.” 

“The hocus-pocus phantasm of a God like another Cerberus, with one body and three heads, had its birth and growth in the blood of thousands and thousands of martyrs... In fact, the Athanasian paradox that one is three, and three but one, is so incomprehensible to the human mind, that no candid man can say he has any idea of it, and how can he believe what presents no idea? He who thinks he does, only deceives himself. He proves, also, that man, once surrendering his reason, has no remaining guard against absurdities the most monstrous, and like a ship without a 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.

“There is a ripeness of time for death,  regarding others as well as ourselves, when it is reasonable we should drop off, and make room for  another growth. When we have lived our generation out, we should not wish to encroach on another.”

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

“A great deal of love given to a few is better than a little to many.”

“It was one of the rules which above all others made Doctr. Franklin the most amiable of men in society, "never to contradict anybody.”

“A morsel of genuine history is a thing so rare as to be always valuable.”

“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]” 

“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.” 

“He has erected a multitude of New Offices, and sent hither swarms of Officers to harass our People, and eat out their substance.”

“And the day will come when the mystical generation of Jesus, by the supreme being as his father in the womb of a virgin will be classed with the fable of the generation of Minerva in the brain of Jupiter. But we may hope that the dawn of reason and freedom of thought in these United States will do away all this artificial scaffolding...

“The ground of liberty is to be gained by inches. We must be contented to secure what we can get from time to time and eternally press forward for what is yet to get. It takes time to persuade men to do even what is for their own good.”

“Truth is great and will prevail if left to herself.”

“Rightful liberty is unobstructed action according to our will within limits drawn around us by the equal rights of others. I do not add 'within the limits of the law' because law is often but the tyrant's will, and always so when it violates the rights of the individual.”