After quoting the paragraph-length definition, Stein adds:
This was written before Freudian psychoanalysis.... If the entry were rewritten today, the only change would be to reframe the diagnosis of vanity into narcissism, the narcissist being the person thinking of no one but oneself. Or, as George Eliot (not Freud or Jung) said, "What we see exclusively, we see out of proportion to reality."I suppose it is arguable that an aspect of George Eliot's genius was her ability to make a tautology sound like a profundity. In any case, it's a pretty good line.