Belief in Numbers
Certain numbers have at all times been invested with mystic significance, e.g., “Three” the “perfect” number, expressive of Beginning, Middle and End; also symbol of Deity. An earlier term of Trinity is Triad, and almost every mythology has a three-fold deity.
That of the ancient Greeks consisted of Zeus, Apollo and Aphrodite, the Egyptian being Osiris, Isis and Horus. The Romans believed the world to be under the rule of three gods—Jupiter (Heaven), Neptune (Ocean), and Pluto (Hades). The first has three thunderbolts—Neptune, the Trident, and Pluto, Cerberus, the triple-headed dog.
Three in number also were the Fates, Furies, Graces, Harpies and Sibylline Books. In the underworld the three judges of hell were Rhadamanthos, Minos and Æacos.