Ralph Waldo Emerson, who went by his middle name Waldo, was an American essayist, lecturer, philosopher, abolitionist, and poet who led the transcendentalist movement of the mid-19th century. He was seen as a champion of individualism and a prescient critic of the countervailing pressures of society. Friedrich Nietzsche considered him "the most gifted of the Americans" and Walt Whitman referred to him as his "master".