Amongst the ancients, the week was shared among the seven planets, each having its own day. This we learn from Dion Cassius, and also from Plutarch (Sympos. lib. iv. c. 7). Herodotus adds, that it was the Egyptians who first discovered what god, that is, what planet, presided over each day; for amongst this people the planets were directors. And hence it is that in most European languages the days of the week are still denominated from the planets.