“I think one travels more usefully when they travel alone, because they reflect more."(Letter to John Banister, Jr., June 19, 1787)”

“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.{Letter to John Adams, from Monticello, 15 August 1820}”

“Leave all the afternoon for exercise and recreation, which are as necessary as reading. I will rather say more necessary because health is worth more than learning.”

“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...{Letter to John Adams, April 11, 1823}”

“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.[Letter to Thomas Law, 13 June 1814]”

“Every day is lost in which we do not learn something useful. Man has no nobler or more valuable possession than time.”

“The most valuable of all talents is that of never using two words when one will do.”