The Masters of the Five Magics was originally taken from a Megadeth song (Five Magics).

Lyrics here: http://www.songfacts.com/lyrics.php?findsong=6524

The important part (for us, that is):

Give me alchemy, give me sorcery
Give me wizardry, thermatology
Electricity, master all of these
Magic if you please, bring him to his knees


So the Five Magics were originally Alchemy, Sorcery, Wizardry, Thermatology, and Electricity. I didn't even know this when I was the (second or third?) mortal leader of Master. I had to ask Rahvin post-imming.

Over the years, with thousands of apps, and huge amounts of serial Master players, leaders needed new questions. Just asking what the Five Magics were was sufficient to start with, but they started embellishing. "Give me an example of Alchemy." "What sort of spell might Thermatology be useful for?" and so on.

Let's take a theoretical timeline: Nepenthe makes Jim the Necro the mortal leader of Master. We go over a few guidelines with Jim, and send him on his merry way. Jim lasts for 4 months as leader. One of his inductees, Bob the Invoker, helps Jim interview apps and such. Eventually, Jim deletes. We make Bob the mortal leader. Now Bob learned everything about induction and such from Jim, but he's got his own twist (no pun intended) to it. He's been interviewing apps left and right even beforehand, and each app throws something new his way, and over time his questions (and the answers he expects) drift away from center. Bob inducts Frank, who months later becomes mortal leader, and inducts Sue, who months later becomes mortal leader, and eventually the Five Magics are Alchemy, Sorcery, Wizardry, Electricity, and Thaumaturgy (instead of Thermatogy). And Thaumaturgy, as opposed to being used for a fireball spell, has somehow become the magic of healing.

That's just one example (that is fairly close to something that happened). Imagine how things got screwy when we just sorta "changed" what the Five Magics are/were (Transmutation, Invocation, Conjuration, Necromancy, and um...something else - I can't remember what the fifth one was. I'm getting old.).