Why does Socrates speak of a single creator god?

[Socratic Spelunker]

In Plato's Dialogues, Socrates occasionally speaks of a single creator god. It was my understanding that Greece was polytheistic (Zeus, etc).

Is this an idea that had spread from other cultures? (Such as when he speaks of reincarnation) Or had Greek culture as a whole gotten away from what we typically view as "Greek Mythology"?

[Ginkgo]

In Plato's Dialogues, Socrates occasionally speaks of a single creator god. It was my understanding that Greece was polytheistic (Zeus, etc).

Is this an idea that had spread from other cultures? (Such as when he speaks of reincarnation) Or had Greek culture as a whole gotten away from what we typically view as "Greek Mythology"?

In Plato's Timaeus there is a demiurge who is the creator of the universe. Probably significant for Neo-Platonism and later Christian concept of God the creator.