“Self-love is no part of morality. Indeed it is exactly its counterpart. It is the sole antagonist of virtue leading us constantly by our propensities to self-gratification in violation of our moral duties to others.”

“It is neither wealth nor splendor, but tranquility and occupation which give happiness.”

“I have examined all the known superstitions of the world,and I do not find in our particular superstition of Christianity one redeeming feature. They are all alike founded on fables and mythology. Millions of innocent men women and children since the introduction of Christianity,have been burnt, tortured, fined and imprisoned. What has been the effect of this coercion? To make one half the world fools and the other half hypocrites; to support roguery and error all over the earth.”

“On matters of style, swim with the current, on matters of principle, stand like a rock.”

“That one generation of men in civil society have no right to make acts to bind another, is a truth that cannot be confused.”

“The laws that forbid the carrying of arms... disarm only those who are neither inclined nor determined to commit crimes.”

“I never considered a difference of opinion in politics, in religion, in philosophy, as cause for withdrawing from a friend.” 

“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.”

“Nothing can stop the man with the right mental attitude from achieving his goal; nothing on earth can help the man with the wrong mental attitude.”

“Even in Europe a change has sensibly taken place in the mind of man. Science has liberated the ideas of those who read and reflect, and the American example has kindled feelings of right in the people.”

“I cannot live without books: but fewer will suffice where amusement, and not use, is the only future object.” 

“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]” 

“our civil rights have no dependance on our religious opinions, any more than our opinions in physics or geometry; that therefore the proscribing any citizen as unworthy the public confidence by laying upon him an incapacity of being called to offices of trust and emolument, unless he profess or renounce this or that religious opinion, is depriving him injuriously of those privileges and advantages to which, in common with his fellow citizens, he has a natural right; that it tends also to corrupt the principles of that very religion it is meant to encourage,”

“Our properties within our own territories [should not] be taxed or regulated by any power on earth but our own.”

“Any Government strong enough to give you what you want, is a Government strong enough to take everything you have!”