Henry David Thoreau
Henry David Thoreau (1817-1862) was an American writer and philosopher, and along with Ralph Waldo Emerson, a major figure in the New England Transcendentalist movement, which was an offshoot of Romanticism. He is perhaps best known for his book Walden (1854), an account of a two-year period during which he lived in relative solitude near the shores of Walden Pond in Massachusetts, and for Civil Disobedience (1849), an essay which depicts his arrest for refusing to pay a poll tax in 1845 that would support the Mexican-American War and slavery. In A Plea for John Brown (1859) he defended the Harper's Ferry Raid.
His work Civil Disobedience would served as inspiration for Gandhi, Tolstoy and modern civil rights leaders in using non-violent means of protest to further a cause.
Thoreau is sometimes mistakenly thought of as a sort of hermit or vagabond, but in fact he was completely serious about carrying on the family business, a factory producing pencils. He made significant improvements in their manufacture and engineered a machine for grinding "plumbago" (graphite) more finely to produce a higher-quality "lead". Thoreau pencils were regarded as being among the best-manufactured in the U.S.
From 1837 until 1861, Thoreau carried a homemade notebook as he wandered about nature in Massachusetts. This amounted to about 2 million words and was his biggest literary project. It was first published in 1906, posthumously.
“Rather than love, than money, than fame, give me truth.”
"If the machine of government is of such a nature that it requires you to be the agent of injustice to another, then, I say, break the law."
"I learned this at least by my experiment: that if one advances confidently in the direction of his dreams, and endeavors to live the life which he has imagined, he will meet with a success unexpected in common hours."
When asked, on his deathbed, whether he had made his peace with God, Thoreau responded, "I did not know we had ever quarreled."
|“||"looking through the stars to see if I could see God behind them."||”|
From A Week on the Concord and Merrimack Rivers
As yesterday and the historical ages are past, as the work of to-day is present, so some flitting perspectives, and demi-experiences of the life that is in nature are in time veritably future, or rather outside to time, perennial, young, divine, in the wind and rain which never die. 
From Walden, Chapter XVIII:
TO THE sick the doctors wisely recommend a change of air and scenery. Thank Heaven, here is not all the world. The buck-eye does not grow in New England, and the mocking-bird is rarely heard here. The wild goose is more of a cosmopolite than we; he breaks his fast in Canada, takes a luncheon in the Ohio, and plumes himself for the night in a southern bayou. Even the bison, to some extent, keeps pace with the seasons cropping the pastures of the Colorado only till a greener and sweeter grass awaits him by the Yellowstone. Yet we think that if rail fences are pulled down, and stone-walls piled up on our farms, bounds are henceforth set to our lives and our fates decided. If you are chosen town-clerk, forsooth, you cannot go to Tierra del Fuego this summer: but you may go to the land of infernal fire nevertheless. The universe is wider than our views of it. 
From Resistance to Civil Government, or Civil Disobedience
I heartily accept the motto,—“That government is best which governs least”; and I should like to see it acted up to more rapidly and systematically. Carried out, it finally amounts to this, which also I believe—“That government is best which governs not at all”; and when men are prepared for it, that will be the kind of government which the will have. Government is at best but an expedient; but most governments are usually, and all governments are sometimes, inexpedient. The objections which have been brought against a standing army, and they are many and weighty, and deserve to prevail, may also at last be brought against a standing government. The standing army is only an arm of the standing government. The government itself, which is only the mode which the people have chosen to execute their will, is equally liable to be abused and perverted before the people can act through it. Witness the present Mexican war, the work of comparatively a few individuals using the standing government as their tool; for in the outset, the people would not have consented to this measure. 
There are a thousand hacking at the branches of evil to one who is striking at the root, and it may be that he who bestows the largest amount of time and money on the needy is doing the most by his mode of life to produce that misery which he strives in vain to relieve.
- Often misquoted as:
For every thousand hacking at the leaves of evil, there is one striking at the root.