The soul of animals is characterized by two faculties, (a) the faculty of discrimination which is the work of thought and sense, and (b) the faculty of originating local movement.
If everything when it occupies an equal space is at rest, and if that which is in locomotion is always occupying such a space at any moment, the flying arrow is therefore motionless.
Even if you must have regard to wealth, in order to secure leisure, yet it is surely a bad thing that the greatest offices, such as those of kings and generals, should be bought. The law which allows this abuse makes wealth of more account than virtue, and the whole state becomes avaricious.
But nothing is yet clear on the subject of the intellect and the contemplative faculty. However, it seems to be another kind of soul, and this alone admits of being separated, as that which is eternal from that which is perishable, while it is clear from these remarks that the other parts of the soul are not separable, as some assert them to be, though it is obvious that they are conceptually distinct.
The attainment of truth is then the function of both the intellectual parts of the soul. Therefore their respective virtues are those dispositions which will best qualify them to attain truth.
So we must lay it down that the association which is a state exists not for the purpose of living together but for the sake of noble actions. Those who contribute most to this kind of association are for that very reason entitled to a larger share in the state than those who, though they may be equal or even superior in free birth and in family, are inferior in the virtue that belongs to a citizen. Similarly they are entitled to a larger share than those who are superior in riches but inferior in virtue.