Q.E.D., short story by Gertrude Stein, one of her earliest works, written in 1903 and published posthumously in 1950 in Things as They Are, a novel in three parts.
Q.E.D. is autobiographical, based on an ill-fated relationship between Adele (Stein), an exuberant young woman, and Helen, who seduces her. Helen eventually rejects Adele for Mabel, a manipulative wealthy woman who uses her money and passionate nature to dominate Helen.