“I cannot live without books.”

“The opinions of men are not the object of civil government, nor under its jurisdiction.” 

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

“I have received the favor of your letter of August 17th, and with it the volume you were so kind as to send me on the Literature of Negroes. Be assured that no person living wishes more sincerely than I do, to see a complete refutation of the doubts I have myself entertained and expressed on the grade of understanding allotted to them by nature, and to find that in this respect they are on a par with ourselves. My doubts were the result of personal observation on the limited sphere of my own State, where the opportunities for the development of their genius were not favorable, and those of exercising it still less so. I expressed them therefore with great hesitation; but whatever be their degree of talent it is no measure of their rights. Because Sir Isaac Newton was superior to others in understanding, he was not therefore lord of the person or property of others. On this subject they are gaining daily in the opinions of nations, and hopeful advances are making towards their reestablishment on an equal footing with the other colors of the human family.”

“With your talents and industry, with science, and that steadfast honesty, which eternally pursues right, regardless of consequences, you may promise yourself everything but health, without which there is no happiness.”

“As Thomas Jefferson proclaimed, “In matters of fashion, swim with the current. In matters of conscience, stand like a rock.”

“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...

“When the people fear the government there is tyranny, when the government fears the people there is liberty.”

“The opinions and beliefs of men follow involuntarily the evidence proposed to their minds.”

“I sincerely believe that banking establishments are more dangerous than standing armies, and that the principle of spending money to be paid by posterity, under the name of funding, is but swindling futurity on a large scale.”

“An enemy generally says and believes what he wishes.” 

“Some men look at constitutions with sanctimonious reverence, and deem them like the ark of the covenant, too sacred to be touched. They ascribe to the men of the preceding age a wisdom more than human, and suppose what they did to be beyond amendment. I knew that age well; I belonged to it, and labored with it. It deserved well of its country. It was very like the present, but without the experience of the present; and forty years of experience in government is worth a century of book-reading; and this they would say themselves, were they to rise from the dead. 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.” 

“I write nothing for publication, and last of all things should it be on the subject of religion. On the dogmas of religion as distinguished from moral principles, all mankind, from the beginning of the world to this day, have been quarrelling, fighting, burning and torturing one another, for abstractions unintelligible to themselves and to all others, and absolutely beyond the comprehension of the human mind. Were I to enter on that arena, I should only add an unit to the number of Bedlamites.

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

“...never [enter] into dispute or argument with another. I never saw an instance of one of two disputants convincing the other by argument. I have seen many, on their getting warm, becoming rude, & shooting one another. ... When I hear another express an opinion which is not mine, I say to myself, he has a right to his opinion, as I to mine; why should I question it? His error does me no injury, and shall I become a Don Quixote, to bring all men by force of argument to one opinion? ... There are two classes of disputants most frequently to be met with among us. The first is of young students, just entered the threshold of science, with a first view of its outlines, not yet filled up with the details & modifications which a further progress would bring to their knoledge. The other consists of the ill-tempered & rude men in society, who have taken up a passion for politics. ... Consider yourself, when with them, as among the patients of Bedlam, needing medical more than moral counsel. Be a listener only, keep within yourself, and endeavor to establish with yourself the habit of silence, especially on politics. In the fevered state of our country, no good can ever result from any attempt to set one of these fiery zealots to rights, either in fact or principle. They are determined as to the facts they will believe, and the opinions on which they will act. Get by them, therefore, as you would by an angry bull; it is not for a man of sense to dispute the road with such an animal.”