1651. Relations between Prudence and Other Virtues.—In the preceding paragraphs the possession of prudence has been joined with the moral virtues. Hence the question presents itself: Can one who lacks the moral virtues possess prudence?
(a) Evil prudence, which chooses ways and means well adapted to some nefarious scheme, and imperfect prudence, which means and judges well but does not strongly resolve, are of course found in sinners. Evil prudence is called after the virtue, because it is a counterfeit of the latter’s goodness, but it is more properly named astuteness or cunning. Its sinfulness is strongly expressed in Rom., viii. 6, which declares that the prudence of the flesh is death. Imperfect prudence is also sinful, for it permits a right judgment to remain ineffectual and is thus recreant to conscience. Examples of evil prudence are the unjust steward mentioned in the Gospel (Luke, xvi. 1), who was wise enough to cheat his master and serve his own interests, and artful swindlers who know how to lure their victims and then escape without detection. Instances of imperfect prudence are persons who deliberate well on the means to overcome assaults of temptation or to escape occasions of sin, but whose resolutions never last.
(b) Indifferent prudence is resourceful in finding ways to accomplish purposes that are good, but that are not necessarily referred to moral aims. Thus, certain men seem to have an uncanny instinct in business or industry of hitting on the methods that lead to success and of acting at the right time, and a similar fact is observed in the fields of science, medicine, art, etc. This kind of ability of knowing and doing the right thing is variously described as insight, discrimination, tact, and is variously explained as luck, genius, industry, etc. But, morally speaking, it is neither virtuous nor sinful, since we find, for example, that men endowed with business acumen or a practical sense of the uses of some art or science devote their talents sometimes to good, sometimes to evil, according to the difference of their characters.
(c) Good prudence is that which in thought and in act functions well with regard to the means for leading a good life. It is only this prudence that receives the name of virtue; and, since it is clear from its concept that it supposes a good life, we must conclude that the virtue of prudence is not found in sinners. It may happen, therefore, that a man is most sagacious in managing temporal affairs, or most skillful in administering the spiritual interests of others, and withal most imprudent, because he neglects his own salvation.
1652. Sins that Cause One to Forfeit the Virtue of Prudence.—(a) Infused prudence is lost by any and every act of mortal sin, whether the sin be against the knowledge had through faith or the knowledge had through reason. (b) Acquired prudence is lost by repeated acts of mortal sin opposed to the knowledge had through reason, but not by one sole act. Thus, a person who through experience and practice has become prudent in overcoming past vices, loses this prudence if he disregards the lessons of the past and exposes himself to the old dangers of mortal sin (see 138).
1653. We may sum up as follows regarding sinners and the possession of the virtue of prudence:
(a) sinners guilty of venial sin only have infused prudence, and also the habit of natural prudence, if they have acquired it by their own efforts;
(b) sinners guilty of mortal sin against supernatural light (e.g., those who sin against faith or hope) have not the infused virtue of prudence, though they may have the acquired virtue;
(c) sinners guilty of habitual mortal sin against natural light (e.g., those who are accustomed to sin against temperance or justice) have neither the infused nor the acquired virtue of prudence. Even one mortal sin, though it will not take away the inclination of the habit of prudence, will deprive one of the perfection of the virtue of prudence, for which it is required that in every act there be a judgment agreeable to a good will.
1654. The Virtue of Infused Prudence in Those Who Are in the State of Grace.—(a) Infants in the state of grace through Baptism possess this virtue in an habitual, but not in an actual manner—that is, on account of their sanctification they have the power, but on account of their want of reason they have not the use of the power.