Why does a wizard's hat have stars and moons?

A quick Google of wizard images brought up dozens of paintings and illustrations with no stars and moons on their Gandalf-style caps.

Maybe there’s some ancient or medieval origin of that imagery, but it seems just as likely that the artists doing that rendering are repeating what they’ve seen in other illustrations. I think the ones you’re thinking of as “classic” are essentially just copying their predecessors, in the same cliche way that cartoons present aliens as “little green men.”

Likewise, I think vampires who haven’t been to the movies won’t know what to do when somebody holds up a pair of sticks crossed at right angles.

@Jeruba But when you search “wizard hat” you do get a lot of results with stars and moons.

I was actually wondering something of the same thing too – like maybe Disney popularized it with the Fantasia short “The Sorcerer’s Apprentice”? But still, I wonder where it came from and why stars and moons.

Well, there’s an astrology connection, for sure.

And the conical hat could symbolize the mind and the (pointed) focusing of the mind. Might also ward off antagonistic influences. I’m just guessing, though—haven’t done any research.

It is indeed Mickey’s lid that is my only reference to the concept.

To indicate that they are smart and powerful. That they control, and travel to the moon, and stars.

That they have the domains of the Heavens and Earth

I’d just stick with the Templar / Islamic imagery of the Moon and Venus, or the shooting star, or whatever.

If Wizards have a religion, I’d look towards Zoroastrianism or the worship of Astaroth.