have taken them step by step through the higher branches of knowledge—Arithmetic, Geometry, and Astronomy—all studied with a view to deeper and ideal truths. By a strict and repeated process of selection, all except those of a resolute and noble nature will be excluded from the number of these "saviours of the State;" again and again these will be tested and examined, and a select list made, till at last the studies of the chosen few will culminate in Dialectic, the coping-stone of all the Sciences. Their souls will then have mounted from gloom to daylight; they will comprehend first principles, and they will be privileged to know and define in its real nature the Idea of Good. At the age of fifty they shall be tested for their final work, and if they come out unscathed from the trial, the remainder of their life shall be passed partly in philosophy, partly in practical politics—till death shall remove them to the Islands of the Blest, and a grateful city shall honour them with monuments and sacrifices.
Such is our State, continues Socrates in the Eighth Book,—perfect, so long as its various parts shall act in harmony; but, like other mortal productions, it is fated to change and decay at a certain period, determined by a mystic number. So also there is a cycle which controls all human births for good or evil; and, in the lapse of years, it must be that our Guardians will miss the propitious time; a degenerate offspring will thus come into being, Education will languish, and there will be a gradual decline in the Constitution.
