In Ben Jonson's "Masque of Christmas", the card game of post and pair is introduced as one of his children, thus characterizing him as a knave. According to the "A Dictionary of Archaic and Provincial Words, Obsolete Phrases and Ancient Customs of the Fourteenth Century", by James Orchard Halliwell-Phillipps, written in 1868, "pur" was the term given to the knave or jack in the game of post and pair. It seems to be formed by an abbreviation of "pair-royal" corrupted into "purrial", similar to how "pair-royal" has since been otherwise corrupted into "prial".