The characteristic feature of the Platonic commonwealth is to specialize the service of each individual in that function for which he is most fit. It is assumed, that each will render due service to the rest, and will receive from them due service in requital. Upon this assumption, Plato pronounces that the community will be happy. Let us grant for the present that this conclusion follows from his premisses. He proceeds forthwith to apply it by analogy to another and a different case--the case of the individual man. He presumes complete analogy between the community and an individual.[33] To a certain extent, the analogy is real: but it fails on the main point which Plato's inference requires as a basis. The community, composed of various and differently endowed members, suffices to itself and its own happiness: "the individual is not sufficient to himself, but stands in need of much aid from others"[34]--a grave fact which Plato himself proclaims as the generating cause and basis of society. Though we should admit, therefore, that Plato's commonwealth is perfectly well-constituted, and that a well-constituted commonwealth will be happy--we cannot from thence infer that an individual, however well-constituted, will be happy. His happiness depends upon others as well as upon himself. He may have in him the three different mental varieties of souls, or three different persons--Reason, Energy, Appetite--well tempered and adjusted; so as to produce a full disposition to just behaviour on his part: but constant injustice on the part of others will nevertheless be effectual in rendering him miserable. From the happiness of a community, all composed of just men--you cannot draw any fair inference to that of one just man in an unjust community. [Footnote 33: The parallel between the Commonwealth and the individual is perpetually reproduced in Plato's reasoning. Republic, ii. pp. 368-369, vii. p. 541 B, ix. pp. 577 C-D, 579 E, &c.] [Footnote 34: Plato, Republic, ii. p. 369 B.]