“I think one travels more usefully when they travel alone, because they reflect more."

“The object most interesting to me for the residue of my life, will be to see you both developing daily those principles of virtue and goodness which will make you valuable to others and happy in yourselves, and acquiring those talents and that degree of science which will guard you at all times against ennui, the most dangerous poison of life. A mind always employed is always happy. This is the true secret, the grand recipe for felicity....In a world which furnishes so many employments which are useful, and so many which are amusing, it is our own fault if we ever know what ennui is...”

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

“The ground of liberty is to be gained by inches. We must be contented to secure what we can get from time to time and eternally press forward for what is yet to get. It takes time to persuade men to do even what is for their own good.”

“The doctor of the future will give no medicine, but will interest his (sic)patient in the care of the human frame, in diet and in the cause and prevention of disease”

“Good wine is a necessity of life for me. ”

“Question with boldness even the existence of a God; because, if there be one, he must more approve of the homage of reason, than that of blind-folded fear.”

“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 probable accumulation of the surpluses of revenue beyond what can be applied to the payment of the public debt... merits the consideration of Congress. Shall it lie unproductive in the public vaults?...Or shall it rather be appropriated to the improvements of roads, canals, rivers, education, and other great foundations of prosperity and union”

“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.”

“You have heard of the new chemical nomenclature endeavored to be introduced by Lavoisier, Fourcroy, &c. Other chemists of this country, of equal note, reject it, and prove in my opinion that it is premature, insufficient and false. These latter are joined by the British chemists; and upon the whole, I think the new nomenclature will be rejected, after doing more harm than good. There are some good publications in it, which must be translated into the ordinary chemical language before they will be useful.”

“If a nation expects to be ignorant and free, in a state of civilization, it expects what never was and never will be.”

“Courts love the people always, as wolves do the sheep”

“A government which can be felt; a government of energy. God send that our country may never have a government, which it can feel.”

“We are not to expect to be translated from despotism to liberty in a featherbed.”