Carlyle was a Scottish philosopher, satirical writer, essayist, translator, historian, mathematician, and teacher. Considered one of the most important social commentators of his time, he presented many lectures during his lifetime with certain acclaim in the Victorian era. One of those conferences resulted in his famous work On Heroes, Hero-Worship, and The Heroic in History where he argued that the key role in history lies in the actions of the "Great Man", claiming that "the history of the world is but the biography of great men".