Prologue

Second Part of the Second Part · Prologue: Prologue. From St. Thomas Aquinas's Summa Theologiae.

After the general treatise of virtues and vices, and other things connected with the matter of morals, we must now consider each of these things in particular. For there is less use in speaking about moral matters in general, since actions are about particular things. Now moral matters can be considered in particular from two points of view. First, from the point of view of the moral matter itself, for instance by considering a particular virtue or a particular vice. Secondly, from the point of view of the special states of man, for instance by considering subjects and superiors, active life and contemplative life, or any other differences among men. Accordingly, we shall treat first in a special way of those matters which pertain to all the states of man; secondly, in a special way, of those matters which pertain to particular states.

As to the first, we must observe that if we were to treat of each virtue, gift, vice, and precept separately, we should have to say the same thing over and over again. For if one wished to treat adequately of this precept: Thou shalt not commit adultery, one would have to inquire about adultery which is a sin, the knowledge of which depends on one's knowledge of the opposite virtue. The shorter and quicker way, therefore, will be if we include the consideration of each virtue, together with its corresponding gift, opposite vice, and affirmative and negative precepts, in the same treatise. Moreover this way of treatment will be suitable to the vices according to their proper species. For it has been shown above that vices and sins differ in species according to the matter or object, and not according to other differences of sins, for instance, in respect of being sins of thought, word, and deed, or committed through weakness, ignorance, or malice, and other like differences. Now the matter about which a virtue works what is right, and about which the opposite vice deviates from the right, is the same.

Accordingly we may reduce the whole of moral matters to the consideration of the virtues, which themselves may be reduced to seven in number. Three of these are theological, and of these we must treat first, while the other four are the cardinal virtues, of which we shall treat afterwards. Of the intellectual virtues there is one, prudence, which is included and numbered among the cardinal virtues. Art, however, does not pertain to moral science, which is concerned with things to be done, for art is right reason about things to be made, as stated above. The other three intellectual virtues, namely wisdom, understanding, and knowledge, agree, even in name, with some of the gifts of the Holy Ghost. Therefore we shall consider them while considering the gifts corresponding to those virtues. The other moral virtues are all in some way reducible to the cardinal virtues, as was explained above. Hence in treating about each cardinal virtue we shall treat also of all the virtues which, in any way whatever, belong to that virtue, as also of the opposite vices. In this way no matter pertaining to morals will be overlooked.