Non prudentia potest esse sine virtute morali quia prudentia non solum est bene consiliativa, sed etiam bene iudicativa et bene praeceptiva: quod esse non potest, nisi removeatur impedimentum passionum corrumpentium iudicium et praeceptum prudentiae; et hoc per virtutem moralem.
Prudence cannot be without moral virtue because prudence not only helps us to be of good counsel, but also to judge and command well: this is not possible unless the impediment of the passions, destroying the judgment and command of prudence, be removed; and this is done by moral virtue.
Aliae virtutes intellectuales sine virtute morali esse possunt, sed prudentia sine virtute morali esse non potest. Cuius ratio est, quia prudentia est recta ratio agibilium: non autem solum in universali, sed etiam in particulari, in quibus sunt actiones.
Other intellectual virtues can, but prudence cannot, be without moral virtue. The reason for this is that prudence is the right reason about things to be done: and this, not merely in general, but also in particulars, which constitute actions.
Recta autem ratio praeexigit principia ex quibus ratio procedit. Oportet autem rationem circa particularia procedere non solum ex principiis universalibus, sed etiam ex principiis particularibus. Circa principia quidem universalia agibilium, homo recte se habet per naturalem intellectum principiorum, per quem homo cognoscit quod nullum malum est agendum; vel etiam per aliquam scientiam practicam. Sed hoc non sufficit ad recte ratiocinandum circa particularia.
Now right reason demands principles from which reason proceeds to argue. And when reason argues about particular cases, it needs not only universal but also particular principles. As to universal principles of action, man is rightly disposed by the natural understanding of principles, whereby he understands that he should do no evil; or again by some practical science. But this is not enough in order that man may reason aright about particular cases.
Contingit enim quandoque quod huiusmodi universale principium cognitum per intellectum vel scientiam, corrumpitur in particulari per aliquam passionem: sicut concupiscenti, quando concupiscentia vincit, videtur hoc esse bonum quod concupiscit, licet sit contra universale iudicium rationis.
For it happens sometimes that the aforesaid universal principle, known by means of understanding or science, is destroyed in a particular case by a passion: thus to one who is swayed by concupiscence, when he is overcome thereby, the object of his desire seems good, although it is opposed to the universal judgment of his reason.
Et ideo, sicut homo disponitur ad recte se habendum circa principia universalia, per intellectum naturalem vel per habitum scientiae, ita ad hoc quod recte se habeat circa principia particularia agibilium, quae sunt fines, oportet quod perficiatur per aliquos habitus secundum quos fiat quodammodo homini connaturale recte iudicare de fine.
Consequently, as by the habit of natural understanding or of science, man is made to be rightly disposed in regard to the universal principles of action, so, in order that he be rightly disposed with regard to the particular principles of action, viz. the ends, he needs to be perfected by certain habits, whereby it becomes connatural, as it were, to man to judge aright to the end.
Et hoc fit per virtutem moralem: virtuosus enim recte iudicat de fine virtutis, quia "qualis unusquisque est, talis finis videtur ei", ut dicitur in III Ethic. Et ideo ad rectam rationem agibilium, quae est prudentia, requiritur quod homo habeat virtutem moralem.
This is done by moral virtue: for the virtuous man judges aright of the end of virtue, because "such as a man is, such does the end seem to him" (Ethic. iii, 5). Consequently the right reason about things to be done, viz. prudence, requires man to have moral virtue.