The astrological symbol most often tied to The Magician is the Planet Mercury.
How well does this correspondence work…? For me personally, I like it pretty well, and I can see why people embrace it. In Astrology, Mercury symbolizes many of our active cognitive functions: thinking, reasoning, data-gathering through the senses. It’s also about communication, whether that be through speech, writing, language, symbols, math. The astrological Mercury is often connected with what we might call “Language Gods” from various mythologies, such as Odin, Hermes, Thoth… In fact, the name of the Planet derives from the name that the Romans gave to their version of the Greek God, Hermes, which name was…Mercury.
And check this out: our word for the middle day of the working week, Wednesday, comes from the Old English name for Odin, which was Woden (“Woden’s Day” –> “Wednesday”). And then look at the name for the same day in several of the Romance languages, and you see a certain pattern emerge: Spanish (Miercoles), French (Mercredi), Italian (Mercoledi), Romanian (Miercuri), Latin (dies Mercurii). Odin and Mercury congregate in that day-name, so now once every week, we quietly acknowledge the importance of the Language God concept as embodied in a name…which would probably please a Language God!
And I can see all of this in The Magician. He channels Divine Energy down into the mundane realms, and gives it specific form and effect via application of will and language. Naming and defining things often grants power – this is why in many mythologies and belief systems, it’s considered dangerous to hand out your true name like a modern-day networker would hand out business cards. You never know who might gain power over you…