“Too old to plant trees for my own gratification, I shall do it for my posterity.”

“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.

“Were I to undertake to answer the calumnies of the newspapers, it would be more than all my own time, and that of 20 aids could effect. For while I should be answering one, twenty new ones would be invented. I have thought it better to trust the justice of my country-men, that they would judge me by what they see of my conduct on the stage where they have placed me.”

“The man who reads nothing at all is better educated than the man who reads nothing but newspapers.”

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

“Our civil rights have no dependence upon our religious opinions more than our opinions in physics or geometry.”

“[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.”

“The happiest moments of my life have been the few which I have passed at home in the bosom of my family.”

“Freedom, the first-born of science.”

“I steer my bark with Hope in the head, leaving Fear astern. My hopes, indeed, sometimes fail; but not oftener than the forebodings of the gloomy.”

“You seem to consider the judges as the ultimate arbiters of all constitutional questions; a very dangerous doctrine indeed, and one which would place us under the despotism of an oligarchy. Our judges are as honest as other men, and not more so. They have, with others, the same passions for party, for power, and the privilege of their corps.... Their power [is] the more dangerous as they are in office for life, and not responsible, as the other functionaries are, to the elective control. The Constitution has erected no such single tribunal, knowing that to whatever hands confided, with the corruptions of time and party, its members would become despots. It has more wisely made all the departments co-equal and co-sovereign within themselves.” 

“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]” 

“Enlighten the people, and tyranny and oppressions of body and mind will vanish like evil spirits at the dawn of day.”

“I consider him [Alexander von Humboldt] the most important scientist whom I have met.”

“The will of the people is the only legitimate foundation of any government, and to protect its free expression should be our first object.”