Longinus (active 1st century CE) is generally regarded as the author of On the Sublime, a work of rhetoric and literary criticism from ancient Greece. Public information about his life is very limited, and his name, identity and the date of the work remain debated among later scholars; this does not prevent On the Sublime from being an important text in the history of Western literary criticism. Written in epistolary form, the book centers on the concept of the sublime and discusses how lofty thought, powerful emotion, the organization of figures of speech, dignified diction and structure combine to produce distinguished writing. The author compares and evaluates passages from ancient Greek poets and orators, and his style combines theoretical reflection with literary sensibility. The work deeply influenced later European literary theory, especially classical and Romantic discussions of genius, passion and the sublime.