Adeimantus, in what amounts to an accusation of Socrates, asserts that the philosophers appear to be either useless or vicious. Plato, as I have suggested, teaches that ultimately this is an appearance that cannot be reversed, and this insures the philosophers' permanent marginality. They appear as useless because they are. They are neither artisans, nor statesmen, nor rhetoricians. They are idlers who contribute nothing to security or posterity. Their peculiar contemplative pleasures are not accessible to the majority of mankind, and they do not provide for the popular pleasures as do the poets.

Commerce and Culture, p. 285. - Giants and Dwarfs (1990)