The analogy in human behavior is sometimes claimed to be that members of a group will attempt to “pull down” (negate or diminish the importance of) any member who achieves success beyond the others, out of envy, conspiracy or competitive feelings, although this is not the behavior being exhibited by the crabs which are simply trying to escape themselves, without any knowledge or understanding of the supposed “success” of their fellow creatures.
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This was one of the most poignant parts of Unseen Academicals, I think.