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

“If Americans desire to be both ignorant and free, they want what never has been and what never will be.”

“I have observed, indeed, generally, that while in protestant countries the defections from the Platonic Christianity of the priests is to Deism, in catholic countries they are to Atheism. Diderot, D'Alembert, D’Holbach, Condorcet, are known to have been among the most virtuous of men. Their virtue, then, must have had some other foundation than the love of God.

“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.”

“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.” 

“The pretense that the workings of the mind, like the actions of the body, are subject to the control of laws, does not seem sufficiently demolished. ... The legitimate powers of government extend to such acts only as are injurious to others.”

“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.” 

“Sometimes it is said that man cannot be trusted with the government of himself. Can he, then, be trusted with the government of others? Or have we found angels in the form of kings to govern him? Let history answer this question.”

“As new discoveries are made, new truths discovered and manners and opinions change with the change of circumstances, institutions must advance also to keep pace with the times.”

“On every question of construction (of the Constitution) let us carry ourselves back to the time when the Constitution was adopted, recollect the spirit of the debates, and instead of trying what meaning may be squeezed out of the text, or invented against it, conform to the probable one in which it was passed.”

“I have sworn upon the altar of god, eternal hostility against every form of tyranny over the mind of man.”

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

“Do not bite at the bait of pleasure till you know there is no hook beneath it.”

“The most fortunate of us, in our journey through life, frequently meet with calamities and misfortunes which may greatly afflict us; and, to fortify our minds against the attacks of these calamities and misfortunes, should be one of the principal studies and endeavours of our lives.”

“Our liberty depends on the freedom of the press, and that cannot be limited without being lost.”