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.
I am not sure I am comfortable with the idea of an entirely context-less "bad concept". I have the annoying habit of answering questions of the type "Is it good/bad, useful/useless, etc." with a counter-question "For which purpose?"
Yes, I understand that rare pathological cases should not crowd out useful generalizations. However given the very strong implicit context (along with the whole framework of preconceived ideas, biases, values, etc.) that people carry around in their heads, I find it useful and sometimes necessary to help/force people break out of their default worldview and consider other ways of looking at things. In particular, ways where good/bad evaluation changes the sign.
To get back to the original point, a concept is a mental model of reality, a piece of a map. A bad concept would be wrong and misleading in the sense that it would lead you to incorrect conclusions about the territory. So a "bad concept" is just another expression for a "bad map". And, um, there are a LOT of bad maps floating around in the meme aether...
"Should" is another word like this. Generally when people say should, they either mean with respect to how best to achieve some goal, or else they're trying to make you follow their moral rules.