In fact, the few statements made on the subject in my popular treatises are quite enough, and accordingly we will adopt them here: as, that the Soul consists of two parts, the Irrational and the Rational (as to whether these are actually divided, as are the parts of the body, and everything that is capable of division; or are only metaphysically speaking two, being by nature inseparable, as are convex and concave circumferences, matters not in respect of our present purpose). And of the Irrational, the one part seems common to other objects, and in fact vegetative; I mean the cause of nourishment and growth (for such a faculty of the Soul one would assume to exist in all things that receive nourishment, even in embryos, and this the same as in the perfect creatures; for this is more likely than that it should be a different one). Now the Excellence of this manifestly is not peculiar to the human species but common to others: for this part and this faculty is thought to work most in time of sleep, and the good and bad man are least distinguishable while asleep; whence it is a common saying that during one half of life there is no difference between the happy and the wretched; and this accords with our anticipations, for sleep is an inactivity of the soul, in so far as it is denominated good or bad, except that in some wise some of its movements find their way through the veil and so the good come to have better dreams than ordinary men. But enough of this: we must forego any further mention of the nutritive part, since it is not naturally capable of the Excellence which is peculiarly human. And there seems to be another Irrational Nature of the Soul, which yet in a way partakes of Reason. For in the man who controls his appetites, and in him who resolves to do so and fails, we praise the Reason or Rational part of the Soul, because it exhorts aright and to the best course: but clearly there is in them, beside the Reason, some other natural principle which fights with and strains against the Reason. (For in plain terms, just as paralysed limbs of the body when their owners would move them to the right are borne aside in a contrary direction to the left, so is it in the case of the Soul, for the impulses of men who cannot control their appetites are to contrary points: the difference is that in the case of the body we do see what is borne aside but in the case of the soul we do not. But, it may be, not the less[42] on that account are we to suppose that there is in the Soul also somewhat besides the Reason, which is opposed to this and goes against it; as to _how_ it is different, that is irrelevant.) But of Reason this too does evidently partake, as we have said: for instance, in the man of self-control it obeys Reason: and perhaps in the man of perfected self-mastery,[43] or the brave man, it is yet more obedient; in them it agrees entirely with the Reason.