Prudence - Article 4

Article 4. Whether prudence is a virtue?

Gregory states (Moral. ii, 49) that prudence, temperance, fortitude and justice are four virtues.

I answer that, As stated above (I-II, 55, 3; I-II, 56, 1) when we were treating of virtues in general, "virtue is that which makes its possessor good, and his work good likewise." Now good may be understood in a twofold sense: first, materially, for the thing that is good, secondly, formally, under the aspect of good. Good, under the aspect of good, is the object of the appetitive power. Hence if any habits rectify the consideration of reason, without regarding the rectitude of the appetite, they have less of the nature of a virtue since they direct man to good materially, that is to say, to the thing which is good, but without considering it under the aspect of good. On the other hand those virtues which regard the rectitude of the appetite, have more of the nature of virtue, because they consider the good not only materially, but also formally, in other words, they consider that which is good under the aspect of good. Now it belongs to prudence, as stated above (1, ad 3; 3) to apply right reason to action, and this is not done without a right appetite. Hence prudence has the nature of virtue not only as the other intellectual virtues have it, but also as the moral virtues have it, among which virtues it is enumerated.

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