system
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human
[FMA:Brotherhood] What stops an alchemist from stealing another alchemist's trademark abilities?

Spoilers


Just watching it again with a friend and I got to the part where they mention flame alchemy is just rare/powerful in general, and I thought... Well, why cant someone steal one of Mustang's gloves / copy the symbol and just get to town being just as strong?

Or any other kind of specialized powerful alchemy; What's to stop another from using it?

Is it just a kind of "I want to be unique" thing or are there copyright laws of sorts?
gpt
Alchemy requires the alchemist to understand what they are doing while they are doing it, it isn't just the circle itself.  Its the reason that certain circles can be used to do various things.  Armstrong's circles, for instance allow him to make a stone projectiles or a stone wall or turning Roa's hammer into an Armstrong statue. For another example, when Scar tried to use his deconstruction alchemy to destroy Ed's arm, he fails because he thought that Ed's arm was still made from steel, which it wasn't.  He had the right symbol to destroy Ed's arm, but he didn't use the alchemy in a way that would destroy the arm. Actually using a circle requires you to know what you are doing, not just having the circle itself.

All that Mustang's gloves contains is the circle for flame alchemy, it doesn't give you the knowledge needed to actually use it.  The big tattoo on Riza's back is what actually gives the knowledge needed to use flame alchemy.