Moral Character (prohairesis)
Long and Sedley (62, commentary on Stoic doctrine):
"A man's moral character is the primary cause of his performing good or bad acts. Each act additionally requires a triggering cause, normally in the form of a sense-impression, since all acts are somehow responses to external circumstances. But because the major share of responsibility belongs to the primary cause, the triggering cause cannot itself be said to necessitate the assent which initiates his action. (It would, for instance, be strange to suggest that a dangled carrot compels a donkey to move, however inevitable that result may be: the principle cause is the donkey's own stupidity.) Now what kind of causation is exerted by fate? From a cosmic perspective, fate is the entire conjunction of causes...But from the point of view of the human individual, there is a sharp divide between himself, comprising his beliefs, moral qualities, etc., and the external world with which he interacts. It would seem absurd to him to become a mere spectator of a single undifferentiated causal nexus in which his own beliefs and attitudes were swallowed up. He must, especially when the apportionment of responsibility is at issue, distinguish himself from the chain of external influences. Thus fate, from his point of view, is the set of external causes which, by acting upon him, work to bring about their destined effects. But since these external causes are no more than triggering causes, he cannot hold them in a strong sense responsible for his actions, let alone sufficient to necessitate them. The primary cause is himself." (pg. 393).
Epictetus, Discourses 1.1.1-12, trans. George Long
Of the things which are in our Power, and not in our Power
"Of all the faculties, you will find not one which is capable of contemplating itself; and, consequently, not capable either of approving or disapproving. How far does the grammatic art possess the contemplating power? As far as forming a judgement about what is written and spoken. And how far music? As far as judging about melody. Does either of them then contemplate itself? By no means. But when you must write something to your friend, grammar will tell you what words you must write; but whether you should write or not, grammar will not tell you. And so it is with music as to musical sounds; but whether you should sing at the present time and play on the lute, or do neither, music will not tell you. What faculty then will tell you? That which contemplates both itself and all other things. And what is this faculty? The rational faculty; for this is the only faculty that we have received which examines itself, what it is, and what power it has, and what is the value of this gift, and examines all other faculties: for what else is there which tells us that golden things are beautiful, for they do not say so themselves? Evidently it is the faculty which is capable of judging of appearances. What else judges of music, grammar, and other faculties, proves their uses and points out the occasions for using them? Nothing else.
"As then it was fit to be so, that which is best of all and supreme over all is the only thing which the gods have placed in our power, the right use of appearances; but all other things they have not placed in our power. Was it because they did not choose? I indeed think that, if they had been able, they would have put these other things also in our power, but they certainly could not. For as we exist on the earth, and are bound to such a body and to such companions, how was it possible for us not to be hindered as to these things by externals?
But what says Zeus? "Epictetus, if it were possible, I would have made both your little body and your little property free and not exposed to hindrance. But now be not ignorant of this: this body is not yours, but it is clay finely tempered. And since I was not able to do for you what I have mentioned, I have given you a small portion of us, this faculty of pursuing an object and avoiding it, and the faculty of desire and aversion, and, in a word, the faculty of using the appearances of things; and if you will take care of this faculty and consider it your only possession, you will never be hindered, never meet with impediments; you will not lament, you will not blame, you will not flatter any person."
moral character (prohairesis); also moral purpose, will. See Discourses 1.4.18-22, 1.12.9, 1.17.21-29, 1.19.8-10/16-22, 1.29.1-4/24/47, 2.1.4-13/39-40, 2.5.4-7, 2.6.24-26, 2.10.8-9/24-30, 2.15.1, 2.16.1-2, 2.22.19-20/27, 2.23.9-29/40, 3.1.40, 3.2.13, 3.3.5-22, 3.4.9, 3.5.1-3, 3.6.5-7, 3.8.1-6, 3.11.1-2, 3.12.4-5, 3.16.15, 3.19.11-3, 3.22.13/100-106, 3.23.5, 3.24.12/56/106/112, 3.26.24, 4.1.84/100, 4.4.1-4/18-23/33/39-40, 4.5.12/23-35, 4.6.9-10, 4.7.8-11, 4.10.1-8, 4.12.7-15, 4.13.21; Handbook 4, 9, 13, 30.
Long, A. A., Sedley, D. N. (1987). The Hellenistic
Philosophers: vol. 1. translations of the principle
sources with philosophical commentary. Cambridge,
England: Cambridge University Press.