I have a pilot pal that used to think that red electricity came out of red wires, and black out of black...as long as one didn't mix them, one was okay. He taught me met, and I tried to give him a feel for all things electrical.
I don't suppose he had all that much confidence in me, we'd grown up together and he'd witnessed my putting an electrolytic across an industrial charger. When it started bulging, we ran, instead of turning the thing off. Loud as a firework- a 1950s one - and took ages to clear up the debris.
He went on to fly the Britannia, so something must have gone in.