We recently established a successful Useful Concepts Repository. It got me thinking about all the useless or actively harmful concepts I had carried around for in some cases most of my life before seeing them for what they were. Then it occurred to me that I probably still have some poisonous concepts lurking in my mind, and I thought creating this thread might be one way to discover what they are.
I'll start us off with one simple example: The Bohr model of the atom as it is taught in school is a dangerous thing to keep in your head for too long. I graduated from high school believing that it was basically a correct physical representation of atoms. (And I went to a *good* high school.) Some may say that the Bohr model serves a useful role as a lie-to-children to bridge understanding to the true physics, but if so, why do so many adults still think atoms look like concentric circular orbits of electrons around a nucleus?
There's one hallmark of truly bad concepts: they actively work against correct induction. Thinking in terms of the Bohr model actively prevents you from understanding molecular bonding and, really, everything about how an atom can serve as a functional piece of a real thing like a protein or a diamond.
Bad concepts don't have to be scientific. Religion is held to be a pretty harmful concept around here. There are certain political theories which might qualify, except I expect that one man's harmful political concept is another man's core value system, so as usual we should probably stay away from politics. But I welcome input as fuzzy as common folk advice you receive that turned out to be really costly.
By harmonic theory I mean the idea proposed by Jean-Philippe Rameau in 1722 of analyzing music as a succession of simultaneities ("chords"), to each of which is assigned a "root", and with the order of chords being governed by relationships among the roots.
The above doesn't make any literal sense, but if what you mean by this is that Baroque music violates Rameau's rules of root progression more often than later music (which, believe it or not, is actually what I think you mean), then this is almost certainly not the case: generally speaking, music gets more complex as you go forward in history, and the more complex it is, the more likely it is to crash Rameau's theory.
(Yes, I know that popular histories tell you that Classical music was simpler than Baroque. This is wrong.)
The reality is that the torpedoes were always damned. Rameau and his theoretical successors mistook certain superficial patterns (which automatically arise in particularly simple musical contexts) for underlying laws. The actual underlying laws were discovered by Schenker and Westergaard.
Would you deny that Baroque music deviates from common chords more often than classical music does?