Prudence - Article 9

Article 9. Whether solicitude belongs to prudence?

It is written (1 Peter 4:7): "Be prudent . . . and watch in prayers." But watchfulness is the same as solicitude. Therefore solicitude belongs to prudence.

I answer that, According to Isidore (Etym. x), a man is said to be solicitous through being shrewd [solers] and alert [citus], in so far as a man through a certain shrewdness of mind is on the alert to do whatever has to be done. Now this belongs to prudence, whose chief act is a command about what has been already counselled and judged in matters of action. Hence the Philosopher says (Ethic. vi, 9) that "one should be quick in carrying out the counsel taken, but slow in taking counsel." Hence it is that solicitude belongs properly to prudence, and for this reason Augustine says (De Morib. Eccl. xxiv) that "prudence keeps most careful watch and ward, lest by degrees we be deceived unawares by evil counsel."


http://www.newadvent.org/summa/3047.htm#article9