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However if you consider an electrical current to be fire that turning on a light is ma’avir, you must consider all electrical fans alarm clock etc muktza as a basis to the current. You can’t pick and chose contradictory kulos. Accepted understanding is that only the glowing filament is a fire not the current, therefore turning on a light is creating a new fire.
What you are saying about the flow of electricity itself not being aish makes sense.