Thamus (mythical King of Egypt)

Thamus was a mythical Pharaoh of Upper Egypt, and appears in Plato's dialogue Phaedrus. According to the story told by Socrates in that dialogue, King Thamus received from the god Thoth the knowledge of writing, but decided not to use it too often, as he reckoned this will damage the ability to remember extensively.

Historicity
It is impossible to determine whether Thamus' character in Plato's dialogue is based on any real Pharaoh that ruled over Egypt. His name does not resemble any known ruler of Lower Egypt. Since Upper Egypt existed as a separate kingdom before it was merged with Lower Egypt around 3,000 BC, it may be conjectured that Plato and other philosophers in his era believed king Thamus lived in the very early history of Egypt.