Social Virtues. Now that the ideal society has been constructed, Plato proposes an
‘elimination method’ for locating justice (427e–428a). Since the society is ideal, it must
(?) contain the standard virtues: wisdom, courage, moderation, and justice. So: what are
the traditional virtues as found in a society?
(a) Wisdom is found in the society’s “sound judgment” about social matters as a whole,
clearly the province of the rulers (428b–429a).
(b) Courage is found in the capacity of a part of the city to preserve its belief about
what is to be feared and what not, namely in the Auxiliaries (429a–430c).
(c) Moderateness is a kind of “harmony” or “orderliness” located in the diﬁusion of
the same opinion throughout the society about who should rule and who should be
So: where is justice? Plato proposes that it is found in the very merit-based criterion itself,
namely in assigning labour-activities on the basis of merit, in which case justice is “the
possession of one’s own and the performance of one’s own task” (433e–434a).
 Individual Virtues (434d–445e). To carry through the analogy of society and the
individual, Plato argues that there are three “parts” of the soul which correspond to the
three classes of society; he then identiﬂes the virtues within each individual soul as the
counterparts of the social virtues described in .
 Proof that there are three parts to the soul:
 [The Principle of Opposites]: “It is clear that the same will not do or suﬁer
opposites, at least with regard to the same and towards the same, at the same
 Thirst is an opposite. (437b1–d7)
 Thirst itself is for drink itself, and not for any special kind of drink. Explanation:
thirst qua thirst is not for hot drink or cold drink, or much drink or little drink,
or drink of any speciﬂc quality. (437d8–e8) (from – below)
 [The Principle of Relatives]: “As to those that are such as to be of something,
those that are somehow qualiﬂed are of something qualiﬂed, it seems to me, but
those that are simply themselves are of something simply itself alone.” (438a7–b2)
 “Thirst is one of those that are