Plato thinks he can prove that his ideal Republic is good; a democrat who accepts the objectivity of ethics may think that he can prove the Republic bad; but anyone agreeing with Thrasymachus will say: There is no question of proving or disproving; the only question is whether you like the kind of State that Plato desires. If you do, it is good for you; if you do not, it is bad for you. If many do and many do not, the decision cannot be made by reason, but only by force, actual or concealed. This is one of the issues of philosophy that are still open; on each side there are men who command respect. But for a very long time the opinion that Plato advocated remained almost undisputed.p. 118.

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