Aristotle was a Greek philosopher from the 4th century BC who made seminal contributions to many fields including metaphysics, logic, ethics, politics, and literary criticism. He wrote Poetics, considered the first work of literary theory, which analyzed Greek tragedy and established principles for understanding dramatic art. In Poetics, Aristotle defines tragedy as an imitation of action that arouses pity and fear through catharsis. He identifies six elements of tragedy - plot, character, diction, thought, melody, and spectacle - and describes how they work together to achieve the desired emotional effect. Aristotle's analysis of tragedy set the standard for dramatic criticism for centuries.