Magic Means Things
Magic doesn't work like physics. Physics runs on math; magic runs on concepts.
Which is not to say that magic is shaped by belief. Rather, it's that magic tends to be accurately modeled by human intuition, in the same way that physics tends to be accurately modeled by math. You can't change magic by changing your beliefs, any more than you can change how physics works by defining new mathematical concepts.
Magic is about things. It's meaningful, on an ontologically basic level, in a way that physics isn't.
If your setting's magic runs on coherent physical principles, it's not really magic. It's science fiction in a pointy hat.
The soul of physics is an equation. The soul of magic is a metaphor.