Prudence - Article 5

Article 5. Whether prudence is a special virtue?

It is distinct from and numbered among the other virtues, for it is written (Wisdom 8:7): "She teacheth temperance and prudence, justice and fortitude."

I answer that, Since acts and habits take their species from their objects, as shown above (I-II, 01, 3; I-II, 18, 2; I-II, 54, 2), any habit that has a corresponding special object, distinct from other objects, must needs be a special habit, and if it be a good habit, it must be a special virtue. Now an object is called special, not merely according to the consideration of its matter, but rather according to its formal aspect, as explained above (I-II, 54, 2, ad 1). Because one and the same thing is the subject matter of the acts of different habits, and also of different powers, according to its different formal aspects. Now a yet greater difference of object is requisite for a difference of powers than for a difference of habits, since several habits are found in the same power, as stated above (I-II, 54, 1). Consequently any difference in the aspect of an object, that requires a difference of powers, will "a fortiori" require a difference of habits. Accordingly we must say that since prudence is in the reason, as stated above (Article 2), it is differentiated from the other intellectual virtues by a material difference of objects. "Wisdom," "knowledge" and "understanding" are about necessary things, whereas "art" and "prudence" are about contingent things, art being concerned with "things made," that is, with things produced in external matter, such as a house, a knife and so forth; and prudence, being concerned with "things done," that is, with things that have their being in the doer himself, as stated above (I-II, 57, 4). On the other hand prudence is differentiated from the moral virtues according to a formal aspect distinctive of powers, i.e. the intellective power, wherein is prudence, and the appetitive power, wherein is moral virtue. Hence it is evident that prudence is a special virtue, distinct from all other virtues.

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