There are no fewer movements in the intellectual or reasonable appetite which is called the will, than there are in the sensitive or sensual, but the first are customarily named affections, the latter passions. The philosophers and pagans did in some manner love God, the state, virtue, sciences; they hated vice, aspired after honours, despaired of escaping death or calumny, were desirous of knowledge, yea even of beatitude after death. They encouraged themselves to surmount the difficulties which cross the way of virtue, dreaded blame, avoided some faults, avenged public injuries, opposed tyrants, without any self-interest. Now all these movements were seated in the reasonable part, since the senses, and consequently, the sensual appetite, are not capable of being applied to these objects, and therefore these movements were affections of the intellectual or reasonable appetite, not passions of the sensual.
How often do we feel passions in the sensual appetite or concupiscence, contrary to the affections which at the same time we perceive in the reasonable appetite or will? How clearly was shown at one and the same time the action of the pleasure of the senses and the displeasure of the will, in that young martyr mentioned by S. Jerom, who, forced to bear the attacks of sensuality, bit off a piece of his tongue and spat it in his tempter's face? How often do we tremble amidst the dangers to which our will carries us and in which it makes us remain? How often do we hate the pleasure in which the sensual appetite takes delight, and love the spiritual good with which that is disgusted? In this consists the war which we daily experience between the spirit and the flesh: between our exterior man, which is under the senses, and the interior which is under the reason; between the old Adam who follows the appetites of his Eve, or concupiscence, and the new Adam who follows heavenly wisdom and holy reason.
The Stoics, as S. Augustine remarks, denying that the wise man can have passions, appear to have confessed that he has affections, which they term eupathies, or good passions, or, as Cicero called them, constancies: for they said the wise man did not covet but desired, had not glee but joy; that he had no fear, but only foresight and precaution, so that he was not moved except by reason and according to reason: for this cause they peremptorily denied that a wise man could ever be sorrowful, that being caused by present evil, whereas no evil can befal a wise man, since no man is hurt but by himself, according to their maxim. And truly, Theotimus, they were not wrong in holding that there are eupathies and good affections in the reasonable part of man, but they erred much in saying that there were no passions in the sensitive part, and that sorrow did not touch a wise man's heart: for omitting the fact that they themselves were troubled in this kind (as was just said), how could it be that wisdom should deprive us of pity, which is a virtuous sorrow and which comes into our hearts in order to make them desire to deliver our neighbour from the evil which he endures? And the wisest man of all paganism, Epictetus, did not hold this error that passions do not rise in the wise man, as S. Augustine witnesses, showing further that the Stoics' difference with other philosophers on this subject was but a mere dispute of words and strife of language.
Now these affections which we feel in our reasonable part are more or less noble and spiritual, according as their objects are more or less sublime, and as they are in a more eminent department of the spirit: for there are affections in us which proceed from conclusions gained by the experience of our senses; others by reasonings from human sciences; others from principles of faith; and finally there are some which have their origin from the simple sentiment of the truth of God, and acquiescence in his will. The first are called natural affections, for who is he that does not naturally desire health, his provision of food and clothing, sweet and agreeable conversation? The second class of affections are named reasonable, as being altogether founded upon the spiritual knowledge of the reason, by which our will is excited to seek tranquillity of heart, moral virtues, true honour, the contemplation of eternal things. The third sort of affections are termed Christian, because they issue from reasonings founded on the doctrine of Our Lord, who makes us love voluntary Poverty, perfect Chastity, the glory of heaven. But the affections of the supreme degree are named divine and supernatural because God himself spreads them abroad in our spirits, and because they regard God and aim at him, without the medium of any reasoning, or any light of nature, as it will be easy to understand from what we shall say afterwards about the acquiescences and affections which are made in the sanctuary of the soul. And these supernatural affections are principally three: the love of the mind for the beautiful in the mysteries of faith, love for the useful in the goods which are promised us in the other life, and love for the sovereign good of the most holy and eternal divinity.