"Plato," History of Political Philosophy, ed. Leo Strauss and Joseph Cropsey, Rand McNally, 1963.  Second Edition: Rand McNally, 1972.  Third Edition, University of Chicago Press, 1987.

Excerpt:

The Nocturnal Council is to be for the city what the mind is for the human individual. To perform its function its members must possess above everything else the most adequate knowledge possible of the single end at which all political action directly or indirectly aims. This end is virtue. Virtue is meant to be one, yet it is also many ; there are four kinds of virtue, and at least two of them-wisdom and courage (or spiritedness )-are radically different from one another. How then can there be a single end of the city ? The Nocturnal Council cannot perform its function if it cannot answer this question, or, more generally and perhaps more precisely stated, the Nocturnal Council must include at least some men who know what the virtues themselves are or who know the ideas of the various virtues as well as what unites them, so that all together can justly be called “virtue” in the singular : is “virtue,” the single end of the city, one or a whole or both or something else ? They also must know, as far as is humanly possible, the truth about the gods. Solid reverence for the gods arises only from knowledge of the soul as well as of the movements of the stars. Only men who combine this knowledge with the popular or vulgar virtues can be adequate rulers of the city: one ought to hand over the city for rule to the Nocturnal Council if it comes into being. Plato brings the regime of the Laws around by
degrees to the regime of the Republic. Having arrived at the end of the Laws, we must return to the beginning of the Republic.

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