Technically, HE was correct. The power was off. You didn't ask him if it was unplugged.
Guy I work with asked me to plug something into an outlet once. I looked in the back, at the wall (where an outlet would be) and told him there wasn't one. He said "well, there was one there a second ago!" so I looked again, back and forth...no outlet. Turns out he was talking about an *extention cord*. I had seen the cord, but didn't look closely at it because I thought it was the cord to another machine.
It's not stupidity, per se, it's all about perception.