It's a complex issue. Obviously the stereotypical glasses-wearing nerd persona is often correct. Sometimes it isn't. So it isn't as simple as one statement. It's a whole chain of events that occur to bring about these types of things. People have tried for a long time to draw pictures like this, but it's never complete. Even if you try to recognize differences by categorizing people as different "types" of myopes, for example, it's still done without knowledge of the whole chain of events. But I don't know the answer either.
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"I conceive that the great part of the miseries of mankind are brought upon them by false estimates they have made of the value of things." - Benjamin Franklin