These virtues, namely, counsel, solertia, sagacity, and sentence, are parts and species of practical prudence. It is the office of prudence to deliberate, which it has and borrows from counsel; promptly and ingeniously to discover some means, from solertia; rightly to judge of the discovered means, from sagacity; and as it were to join the voice of equity and justice to judgment, from sentence. But there remains one office, namely, to prescribe the circumstances for the action of each virtue, which it claims as proper and germane to itself.
The acts of prudence are five:
Deliberating, whence counsel, which is euboulia
Discovering a means swiftly, if that be the task, whence solertia, which is eustochia
Rightly judging about the means, whence sagacity, which is synesis
Fulfilling the judgment, whence sentence, which is gnome
Prescribing the circumstances of action, whence is drawn the proper name of prudence.
(I am putting this here mostly so I can easily find the reference again.)
