Walden & Civil Disobedience by Henry David Thoreau.
In 1845, Thoreau moved to a cabin that he built with his own hands along the shores of Walden Pond in Massachusetts. Shedding the trivial ties that he felt bound much of humanity, Thoreau reaped from the land both physically and mentally, and pursued truth in the quiet of nature. In Walden, he explains how separating oneself from the world of men can truly awaken the sleeping self. Thoreau holds fast to the notion that you have not truly existed until you adopt such a lifestyle—and only then can you reenter society, as an enlightened being.
In Civil Disobedience Thoreau asserts that because governments are typically more harmful than helpful, they therefore cannot be justified. Democracy is no cure for this, as majorities simply by virtue of being majorities do not also gain the virtues of wisdom and justice. The judgment of an individual's conscience is not necessarily inferior to the decisions of a political body or majority, and so "it is not desirable to cultivate a respect for the law, so much as for the right.
The only obligation which I have a right to assume is to do at any time what I think right.... Law never made men a whit more just; and, by means of their respect for it, even the well-disposed are daily made the agents of injustice." He adds, "I cannot for an instant recognize as my government that which is the slave's government also."
The government, according to Thoreau, is not just a little corrupt or unjust in the course of doing its otherwise-important work, but in fact the government is primarily an agent of corruption and injustice. Because of this, it is "not too soon for honest men to rebel and revolutionize."
He exhorts people not to just wait passively for an opportunity to vote for justice, because voting for justice is as ineffective as wishing for justice; what you need to do is to actually be just. This is not to say that you have an obligation to devote your life to fighting for justice, but you do have an obligation not to commit injustice and not to give injustice your practical support.
Paying taxes is one way in which otherwise well-meaning people collaborate in injustice. People who proclaim that the war in Mexico is wrong and that it is wrong to enforce slavery contradict themselves if they fund both things by paying taxes. Thoreau points out that the same people who applaud soldiers for refusing to fight an unjust war are not themselves willing to refuse to fund the government that started the war.