“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...”

“Determine never to be idle. No person will have occasion to complain of the want of time, who never loses any. It is wonderful how much may be done, if we are always doing.”

“...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.”

“I am conscious that an equal division of property is impracticable. But the consequences of this enormous inequality [in Europe] producing so much misery to the bulk of mankind, legislators cannot invent too many devices for subdividing property,...[One] means of silently lessening the inequality of property is to exempt all from taxation below a certain point, and to tax the higher portions of property in geometrical progression as they rise.”

“Nothing gives one person so much advantage over another as to remain always cool and unruffled under all circumstances.”

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

“I felt enough of the effect of withdrawing from the world then, to see that it led to an antisocial and misanthropic state of mind, which severely punished him who gives in to it. And it will be a lesson I never shall forget as to myself.”

“In every country and in every age, the priest has been hostile to liberty. He is always in alliance with the despot, abetting his abuses in return for protection to his own.”

“Any Government strong enough to give you what you want, is a Government strong enough to take everything you have!” 

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

“History, I believe, furnishes no example of a priest-ridden people maintaining a free civil government. This marks the lowest grade of ignorance of which their civil as well as religious leaders will always avail themselves for their own purposes.

“When once we quit the basis of sensation, all is in the wind. To talk of immaterial existences is to talk of nothings. To say that the human soul, angels, god, are immaterial, is to say they are nothings, or that there is no god, no angels, no soul. I cannot reason otherwise: but I believe I am supported in my creed of materialism by Locke, Tracy, and Stewart.

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

“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.”

“The force of public opinion cannot be resisted when permitted freely to be expressed. The agitation it produces must be submitted to.”