I have sworn upon the altar of God, eternal hostility against every form of tyranny over the mind of man.

Letter to Dr. Benjamin Rush, September 23, 1800

Jefferson endorsed the concepts of the Separation of Powers, and that each branch of government should have checks upon the others. Hence, in his Notes on Virginia, in answering Query XIII, he said the following: 

"The concentrating these [the legislative, executive, and judiciary powers] in the same hands is precisely the definition of despotic government. . . . An elective despotism was not the government we fought for, but one which should not only be founded on free principles, but in which the powers of government should be so divided and balanced among several bodies of magistracy, as that no one could transcend their legal limits, without being effectually checked and restrained by the others. For this reason that convention which passed the ordinance of government, laid its foundation on this basis, that the legislative, executive, and judiciary departments should be separate and distinct, so that no person should exercise the powers of more than one of them at the same time."

He expressed his concerns about the Virginia Constitution at the time (c. 1782), about too much power in the hands of the legislature. Such power and the control of the money that came with it, he said

". . . will soon be discovered to be sources of wealth and dominion to those who hold them; distinguished, too, by this tempting circumstance, that they are the instrument, as well as the object of acquisition. With money we will get men, said Caesar, and with men we will get money. Nor should our assembly be deluded by the integrity of their own purposes, and conclude that these unlimited powers will never be abused, because themselves are not disposed to abuse them. They should look forward to a time, and that not a distant one, when a corruption in this, as in the country from which we derive our origin, will have seized the heads of government, and be spread by them through the body of the people; when they will purchase the voices of the people, and make them pay the price. . . The time to guard against corruption and tyranny, is before they shall have gotten hold of us. It is better to keep the wolf out of the fold, than to trust to drawing his teeth and claws after he shall have entered." [emphasis added]

Jefferson also warned, that "The natural progress of things is for liberty to yield and government to gain ground." (Letter to Colonel Carrington, May 27, 1788.)  It follows that only a moral and vigilent people can remain free. He made it clear that the greatest enemy to freedom, is government.

Jefferson's good friend and Secretary of State, James Madison, identified another enemy in The Federalist Papers, No. 51, as crime and anarchy, "a state of nature, where the weaker individual is not secured against the violence of the stronger." However, he also likens pure or complete democracy to anarchy, condemning a society whose form or government structure allows "the stronger faction [to] readily unite and oppress the weaker." Indeed, in The Federalist Papers, No. 10, Madison says that "democracies have ever been spectacles of turbulence and contention; have ever been found incompatible with personal security or the rights of property; and have in general been as short in their lives as they have been violent in their deaths." When Franklin, at the conclusion of the Constitutional Convention, was asked what kind of government they had given America, he replied, "A republic, if you can keep it." Hence, the founders designed our government, not to create a democracy, in which they did not believe, but to preserve liberty.

In one of Jefferson's greatest writings, his A Summary View of the Rights of British America (1774), he said:

"The God who gave us life, gave us liberty at the same time: the hand of force may destroy, but cannot disjoin them."