From 1265-1274, the famous Catholic theologian Thomas Aquinas (c. 1225-1274) worked on his most famous work, Summa Theologica, which remained unfinished at his death. Within this massive work are Aquinas's five proofs of the existence of God: there must be a first mover, unmoved; a first cause in the chain of causes; an absolutely necessary being; an absolutely perfect being; and a rational designer. Whether one accepts Aquinas's arguments or not is not the issue at stake here, it is how Ellis Weiner humorously applies these arguments to prove the existence of Santa Claus.