(c) It is a saying, that "no mortal is always wise." There are times when reason's utterance is faint from weariness and vexation. Then, unless a man has acquired an almost mechanical habit of obeying reason in the conduct of his will and passions, he will in such a conjuncture act inconsiderately and do wrong. That habit is moral virtue. Moral virtue is as the fly-wheel of an engine, a reservoir of force to carry the machine past the "dead points" in its working. Or again, moral virtue is as discipline to troops suddenly attacked, or hard pressed in the fight. 5. Therefore, besides the habits in the intellect that bear the name of _intellectual virtues_, the virtuous man must possess other habits, as well in the will, that this power may readily embrace what the understanding points out to be good, as in the sensitive appetite in both its parts, concupiscible and irascible, so far forth as appetite is amenable to the control of the will, that it may be so controlled and promptly obey the better guidance. These habits in the will and in the sensitive appetite are called _moral virtues_, and to them the name of _virtue_ is usually confined. _Readings_.--St. Thos., 1a 2æ, q. 71, art. 1, in corp.; _ib_., q. 58, art. 2; _ib_., q. 58, art. 3, in corp., ad 3; _ib_., q. 56, art. 4, in corp., ad 1-3. SECTION III.--_Of the Difference between Virtues, Intellectual and Moral_. 1. St. Thomas (1a 2æ, q. 56, art. 3, in corp.) [Footnote 4] draws this difference, that an intellectual virtue gives one a facility in doing a good act; but a moral virtue not only gives facility, but makes one put the facility in use. Thus a habit of grammar he says, enables one readily to speak correctly, but does not ensure that one always shall speak correctly, for a grammarian may make solecisms on purpose: whereas a habit of justice not only makes a man prompt and ready to do just deeds, but makes him actually do them. Not that any habit necessitates volition. Habits do not necessitate, but they facilitate the act of the will. (s. i., nn. 1, 2, 8, pp. 64, 68.) [Footnote 4: By _doing good_ St. Thomas means the determination of the appetite, rational or sensitive, to good. He says that intellectual virtue does not prompt this determination of the appetite. Of course it does not: it prompts only the act of the power wherein it resides: now it resides in the intellect, not in the appetite; and it prompts the act of the intellect, which however is cot always followed by an act of appetite in accordance with it.]