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

“Of all machines, the human heart is the most complicated and inexplicable.”

“The rich alone use imported articles, and on these alone the whole taxes of the General Government are levied...and its surplus applied to canals, roads, schools, etc., the farmer will see his government supported, his children educated, and the face of his country made a paradise by the contributions of the rich alone, without his being called on to spend a cent from his earnings.”

“I do not take a single newspaper, nor read one a month, and I feel myself infinitely the happier for it.” 

“Whenever the people are well-informed, they can be trusted with their own government”

“Whatever enables us to go to war, secures our peace”

“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.” 

“Even in Europe a change has sensibly taken place in the mind of man. Science has liberated the ideas of those who read and reflect, and the American example has kindled feelings of right in the people.”

“It is neither wealth nor splendor; but tranquility and occupation which give you happiness.”

“Follow truth wherever it may lead you.”

“I would rather be exposed to the inconveniences attending too much liberty than to those attending too small a degree of it.”

“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.”

“Later, he told his nephew that religion required careful thought, not reflexive acceptance. "Fix reason firmly in her seat, and call to her tribunal every fact, every opinion. Question with boldness even the existence of a God; because, if there be one, he must more approve the homage of reason, than that of blindfolded fear”

“All that is necessary for a student is access to a library.”

“It is more dangerous that even a guilty person should be punished without the forms of law than that he should escape.”