Ralph Waldo Emerson (May 25, 1803 April 27, 1882) was a famous American writer and poet. He's considered to be the father of the Transcendentalist movement, which stressed self-reliance and the inner good of man. Emerson encouraged Americans to think for themselves rather than copy what the Europeans were doing, and he played a huge role in shaping a unique American philosophy. Famous for being very quotable - it was Emerson who came up with the name "the shot heard round the world" to describe the Battles of Lexington and Concord.
Emerson was also Henry David Thoreau's mentor, and the godfather to famous psychologist William James.