I am not myself apt to be alarmed at innovations recommended by reason. That dread belongs to those whose interests or prejudices shrink from the advance of truth and science.

Thomas Jefferson, letter to Dr. John Manners, February 22, 1814

The Christian priesthood, finding the doctrines of Christ levelled to every understanding, and too plain to need explanation, saw, in the mysticisms of Plato, materials with which they might build up an artificial system which might, from its indistinctness, admit everlasting controversy, give employment for their order, and introduce it to profit, power and preeminence. The doctrines which flowed from the lips of Jesus himself are within the comprehension of a child; but thousands of volumes have not yet explained the Platonisms engrafted on them: and for this obvious reason that nonsense can never be explained.

Thomas Jefferson, letter to John Adams, July 5, 1814

Mischief may be done negatively as well as positively. Of this a cabal in the Senate of the U.S. has furnished many proofs. Nor do I believe them necessary to protect the wealthy; because enough of these will find their way into every branch of the legislation to protect themselves. From 15. to 20. legislatures of our own, in action for 30. years past, have proved that no fears of an equalisation of property are to be apprehended from them.

Thomas Jefferson, letter to John Adams, October 28, 1813

I hold it, therefore, certain, that to open the doors of truth, and to fortify the habit of testing everything by reason, are the most effectual manacles we can rivet on the hands of our successors to prevent their manacling the people with their own consent.

Thomas Jefferson, letter to Judge John Tyler, June 28, 1804

While in Europe, I often amused myself with contemplating the characters of the then reigning sovereigns of Europe. Louis the XVI was a fool, of my own knowledge, and in despite of the answers made for him at his trial. The King of Spain was a fool, and of Naples the same. They passed their lives in hunting, and despatched two couriers a week, one thousand miles, to let each other know what game they had killed the preceding days. The King of Sardinia was a fool. All these were Bourbons. The Queen of Portugal, a Braganza, was an idiot by nature. And so was the King of Denmark. Their sons, as regents, exercised the powers of government. The King of Prussia, successor to the great Frederick, was a mere hog in body as well as in mind. Gustavus of Sweden, and Joseph of Austria, were really crazy, and George of England you know was in a straight waistcoat. There remained, then none but old Catherine, who had been too lately picked up to have lost her common sense. In this state Buonaparte found Europe; and it was this state of its rulers which lost it with scarce a struggle.

Thomas Jefferson, letter to Governor John Langdon, March 5, 1810

This was only about one year after Jefferson left the presidency. Maybe it’s a good thing there weren’t many meetings between heads of state back then.

No man on earth has less taste or talent for criticism than myself, and least and last of all should I undertake to criticise works works on the Apocalypse. It is between 50. and 60. years since I read it, and I then considered it as merely the ravings of a Maniac, no more worthy, nor capable of explanation than the incoherences of our own nightly dreams. … There is not coherence enough in them to countenance any suite of rational ideas. You will judge therefore from this how impossible I think it that either your explanation, or that of any man in the heavens above, or on the earth beneath, can be a correct one. What has no meaning admits no explanation.

Thomas Jefferson, letter to Alexander Smyth, January 17, 1825

I suppose the crippled state of Congress is not new to you. We have only 9 states present, 8. of whom are represented by two members each, and of course, on all great questions not only an unanimity of States but of members is necessary. An unanimity which can never be obtained on a matter of any importance. The consequence is that we are wasting our time & labour in vain efforts to do business.

Thomas Jefferson, letter to George Washington, March 15, 1784

So when a system is set up to allow a minority to easily block action almost nothing gets done. Imagine that.

A strong body makes the mind strong. As to the species of exercise, I advise the gun. It gives boldness, enterprise, and independence to the mind. Games played with the ball, and others of that nature, are too violent for the body, and stamp no character on the mind. Let your gun therefore be the constant companion of your walks.

Thomas Jefferson, letter to Peter Carr, August 19, 1785

Games played with balls are too violent, but guns are okay???? I hope Mr. Jefferson doesn’t mind my questioning his call on this one.

If we did a good act merely from the love of God and a belief that it is pleasing to Him, whence arises the morality of the Atheist? It is idle to say, as some do, that no such being exists. We have the same evidence of the fact as of most of those we act on, to-wit: their own affirmations, and their reasonings in support of them. 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.

Thomas Jefferson, letter to Thomas Law, June 13, 1814

I hold it, therefore, certain, that to open the doors of truth, and to fortify the habit of testing everything by reason, are the most effectual manacles we can rivet on the hands of our successors to prevent their manacling the people with their own consent.

Thomas Jefferson, letter to Judge John Tyler, June 28, 1804

Test things by reason. Texas Republican platform take note.