What does this quote from Thomas Jefferson The tree of liberty must be refreshed from time to time with the blood of patriots and tyrants It is a natural manure mean?

Answer 1

It is a partial quote, actually. It is taken from a letter Jefferson wrote to William Smith in 1787 in reference to an uprising in Massachusetts after the American Revolution. A more full quote:

"Yet where does this anarchy exist? Where did it ever exist, except in the single instance of Massachusetts? And can history produce an instance of a rebellion so honourably conducted? I say nothing of it's motives. They were founded in ignorance, not wickedness. God forbid we should ever be twenty years without such a rebellion. The people cannot be all, and always, well informed. The part which is wrong will be discontented, in proportion to the importance of the facts they misconceive. If they remain quiet under such misconceptions, it is lethargy, the forerunner of death to the public liberty. And what country can preserve its liberties, if it's rulers are not warned from time to time, that this people preserve the spirit of resistance? Let them take arms. The remedy is to set them right as to the facts, pardon and pacify them. What signify a few lives lost in a century or two? The tree of liberty must be refreshed from time to time, with the blood of patriots and tyrants. It is its natural manure."

Jefferson is referring, specifically, to the Shays' Rebellion. If you look at the context of the quote, it appears that Jefferson actually believed the men who took arms were essentially wrong about the facts, but he still considered them patriotic for making their voices heard. Jefferson felt it was important that the government be kept in check, even if those keeping them in check were not necessarily in the right. It wasn't being in the "right" that kept the people free, but rather the fact that they had a voice and used it.

The specific meaning to the last part of the quote, the piece most often quoted, isn't an incitement to violence against the state (which it has unfortunately been sometimes misconstrued to be), but rather seems an acceptance of some degree of violence as a necessary element to keeping freedom safe... a "necessary evil", if you will.

What is often missed is that Jefferson immediately preceded the most quoted part of the letter with his solution for the state: "to set them right as to the facts, pardon and pacify them."