 Magician and writer John Scarne believes gin rummy to have evolved from 19th-century whiskey poker (a game similar to Commerce, with players forming poker combinations) and to have been created with the intention of being faster than standard rummy but less spontaneous than knock rummy.David Parlett finds Scarne's theory to be "highly implausible", and considers the game of Conquian to be gin rummy's forerunner.Gin rummy is played with a standard 52-card pack of cards.