From what has been said then it is clear that one cannot be, strictly speaking, good without Practical Wisdom nor Practically-Wise without moral goodness.
And by the distinction between Natural and Matured Virtue one can meet the reasoning by which it might be argued “that the Virtues are separable because the same man is not by nature most inclined to all at once so that he will have acquired this one before he has that other:” we would reply that this is possible with respect to the Natural Virtues but not with respect to those in right of which a man is denominated simply good: because they will all belong to him together with the one faculty of Practical Wisdom.
It is plain too that even had it not been apt to act we should have needed it, because it is the Excellence of a part of the Soul; and that the moral choice cannot be right independently of Practical Wisdom and Moral Goodness; because this gives the right End, that causes the doing these things which conduce to the End.
Then again, it is not Master of Science (i.e. of the superior part of the Soul), just as neither is the healing art Master of health; for it does not make use of it, but looks how it may come to be: so it commands for the sake of it but does not command it.
The objection is, in fact, about as valid as if a man should say πολιτικὴ governs the gods because it gives orders about all things in the communty.
APPENDIX
On ἐπισπήμη, from I. Post. Analyt. chap. i. and ii.