Hail To Reason (April 18, 1958 - February 24, 1976) was an American thoroughbred racehorse and an influential sire. He was bred in Kentucky by the Bieber-Jacobs Stable, a partnership of prominent horsemen, Isadore Bieber and Hirsch Jacobs. He was sired by the English stakes winner Turn-To, a grandson of the very influential sire Nearco.