An Essay on Criticism is one of the first major poems written by the English writer Alexander Pope (1688–1744). It is the source of the famous quotations "To err is human, to forgive divine," "A little learning is a dang'rous thing" (frequently misquoted as "A little knowledge is a dang'rous thing"), and "Fools rush in where angels fear to tread." It first appeared in 1711 after having been written in 1709, and it is clear from Pope's correspondence that many of the poem's ideas had existed in prose form since at least 1706. Composed in heroic couplets (pairs of adjacent rhyming lines of iambic pentameter) and written in the Horatian mode of satire, it is a verse essay primarily concerned with how writers and critics behave in the new literary commerce of Pope's contemporary age. The poem covers a range of good criticism and advice, and represents many of the chief literary ideals of Pope's age.