Pierre; or, The Ambiguities is the seventh book by American writer Herman Melville, first published in New York in 1852. The novel, which uses many conventions of Gothic fiction, develops the psychological, sexual, and family tensions between Pierre Glendinning; his widowed mother; Glendinning Stanley, his cousin; Lucy Tartan, his fiancee; and Isabel Banford, who is revealed to be his half-sister. When Pierre Glendinning's lifelong desire for a sister is seemingly realized on the eve of his marriage, his world is suddenly turned upside down, for he must choose between acknowledging his illegitimate half-sister or perpetuating his unsullied family legacy. Melville unfolds the story of an idealistic young man whose steadfast beliefs lead him to destroy his world and himself.