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

“If the present Congress errs in too much talking, how can it be otherwise in a body to which the people send 150 lawyers, whose trade it is to question everything, yield nothing, & talk by the hour? That 150 lawyers should do business together ought not to be expected.”

“Everything predicted by the enemies of banks, in the beginning, is now coming to pass. We are to be ruined now by the deluge of bank paper. It is cruel that such revolutions in private fortunes should be at the mercy of avaricious adventurers, who, instead of employing their capital, if any they have, in manufactures, commerce, and other useful pursuits, make it an instrument to burden all the interchanges of property with their swindling profits, profits which are the price of no useful industry of theirs.”

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

“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.”

“The care of human life and happiness, and their destruction is the first and only legitimate object of a good government.”

“I am a great believer in luck, and I find the harder I work, the more I have of it.”

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

“I know no safe depository of the ultimate powers of the society but the people themselves ; and if we think them not enlightened enough to exercise their control with a wholesome discretion, the remedy is not to take it from them, but to inform their discretion by education. This is the true corrective of abuses of constitutional power.” 

“I am savage enough to prefer the woods, the wilds, and the independence of Monticello, to all the brilliant pleasures of this gay capital [Paris].”

“The greatest service which can be rendered any country is to add a useful plant to its culture.

“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]” 

“Every day is lost in which we do not learn something useful. Man has no nobler or more valuable possession than time.”

“But every difference of opinion is not a difference of principle.”

“‎We must make our choice between economy and liberty or confusion and servitude...If we run into such debts, we must be taxed in our meat and drink, in our necessities and comforts, in our labor and in our amusements...if we can prevent the government from wasting the labor of the people, under the pretense of caring for them, they will be happy.”