“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.” 

“Whenever any form of government becomes destructive of these ends [life, liberty, and the pursuit of happiness] it is the right of the people to alter or abolish it, and to institute new government...” 

“Resolved ... that it would be a dangerous delusion were a confidence in the men of our choice to silence our fears for the safety of our rights: that confidence is everywhere the parent of despotism — free government is founded in jealousy, and not in confidence;”

“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]” 

“The art of life is the art of avoiding pain.”

“A little rebellion now and then is a good thing.”

“The legitimate powers of government extend to such acts only as are injurious to others. It does me no injury for my neighbor to say there are twenty gods or no god. It neither picks my pocket nor breaks my leg.”

“I sincerely believe the banking institutions having the issuing power of money, are more dangerous to liberty than standing armies.”

“If, therefore, from the settlement of the Saxons, to the introduction of Christianity among them, that system of religion could not be a part of the common law, because they were not yet Christians; and if, having their laws from that period to the close of the common law, we are able to find among them no such act of adoption; we may safely affirm (though contradicted by all the judges and writers on earth) that Christianity neither is, nor ever was, a part of the common law.

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

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

“All eyes are opened, or opening, to the rights of man. The general spread of the light of science has already laid open to every view the palpable truth that the mass of mankind has not been born with saddles on their backs, nor a favored few booted and spurred, ready to ride them legitimately, by the grace of God. These are grounds of hope for others. For ourselves, let the annual return of this day forever refresh our recollection of these rights, and an undiminished devotion to them.”

“I am convinced our own happiness requires that we should continue to mix with the world, and to keep pace with it as it goes. "

“[Christianity is] the most ... perverted system that ever shone on man.”

“It is reasonable that everyone who asks justice should do justice”