208 years ago today, on July 12th, 1817 (May 28th, 1817 in the lunar calendar), American writer Henry David Thoreau was born. Henry David Thoreau (1817-1862), an American writer and philosopher, is the author of the famous essay collection Walden and the essay On the Citizen's Right to Disobey (also translated as Passive Resistance and On Citizen's Disobedience). Thoreau was born in Concord, Massachusetts, on July 12, 1817. He graduated from Harvard University in 1837 and was a student with excellent academic performance. After graduation, he returned to his hometown to teach as a profession. From 1841, he stopped teaching and turned to writing. With the support of Ralph Waldo Emerson, Thoreau stayed in Concord and began his practice of transcendentalism. During this period, Thoreau gave up poetry creation and began to write essays. At first, he wrote manuscripts for the transcendentalist publication Dial, and then his articles were published in newspapers and magazines all over the world. Besides being honored by some as the first environmentalist, Thoreau was also an influential philosopher concerned about human existence. His famous paper On the Citizen's Right to Disobey influenced Tolstoy and Mahatma Gandhi. On July 4, 1845, Thoreau began a two-year experiment. He moved to the secondary forest on the beautiful Walden Pond, not far from his hometown of Concord, and tried a simple seclusion. He left Walden on September 6, 1847, to re-join the family of his friend and mentor, Ralph Waldo Emerson, who lived in Concord City. Walden, a collection of essays published in 1854, details his two years and two months on the shores of Walden. Although he graduated from the world-famous Harvard University, he didn't choose to make a fortune in business or become a star in politics. Instead, he calmly chose Walden Lake, freedom and leisure of his mind. He built a wooden house, opened up wasteland and farmed land, wrote and read books, and lived a very simple and primitive life. At different times, Thoreau lived by teaching and working. He once worked in his family's pencil factory, and invented a machine that could simplify production and reduce costs. Thoreau was a student and friend of Ralph Waldo Emerson, and influenced by Emerson, Thoreau was also a transcendentalist. Thoreau had traveled to Cape Cod, Agiokochuk, and Mt. Katahdin in Maine. One trip to Maine visited Ktaadn, Chesuncook, and the eastern branch of the Penobscot River. Thoreau died of lung disease in his hometown of Concord City on May 6, 1862 (age 44) and was buried at Sleepy Hollow Cemetery in Concord City, Massachusetts. His book Walden has been popular all over the world for 150 years.