Misconceptions

I've blogged about logic errors in the past, and some of what I'm going to post about today I may have posted in the past, but not in as much detail.
I had someone tell me once "You can't play 'Taps' on a bugle. I know because I play the cornet, and a cornet is just like a bugle, except that it has valves. I can play 'Taps' on the cornet, but I have to use the valves, so you can't really play 'Taps' on the bugle." I asked him if he was aware that 'Taps' was written for the bugle, and he said he was, but that it was fake. It seems to me that either he was very confused, or a whole bunch of bugle players are...
I had a school project once that involved a team of students planning a theoretical medical clinic for a low-income neighborhood. I think we came up with some reasonable guesstimates for how big a facility we would need, how big the staff should be, etc. The rub came when we were trying to establish a salary for the doctor. I felt that we might be able to coax a civic-minded doctor into working at this clinic for $60,000. One of my teammates told me I was being extravagant, "My mother is a nurse, and she only makes $18,000." "That's because she's a nurse. We're talking about a doctor." "It's the same thing. Nurses have to go through just as much training as doctors do." "Then why aren't they doctors?" Eventually I was overruled, and we ended up getting a good grade, even though the teacher couldn't understand how we thought we could get a doctor on board for only $18,000 (she liked the rest of it, though).
I also had a classmate tell me that secretaries are the most important part of any big business. She knew this because her mom was a secretary. They do all the real work. I can understand that, to some extent, she's right. A good secretary takes care of a lot of details, so that the executive doesn't have to be bothered with them. A good secretary types, and files, and can find things later when they need them. The executive makes decisions. To be honest, there are probably a lot of secretaries out there that have been in the business long enough that they could make better decisions, just based on experience. But that isn't what they were hired to do. Maybe somebody smart should check out his secretarial staff for smart people next time he needs a new executive. I'm not holding my breath, though, and I don't think you should either.