Therefore, justice combined with practical wisdom will command all the confidence we can desire; justice without wisdom will be able to do much; wisdom without justice will be of no avail at all.
 Marcus Tullius Cicero, On Duties (44 BC). copy citation

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Author Marcus Tullius Cicero
Source On Duties
Topic wisdom justice
Date 44 BC
Language English
Reference
Note Translated by Walter Miller
Weblink http://www.constitution.org/rom/de_officiis.htm

Context

“{34} Of these two qualities, then, justice has the greater power to inspire confidence; for even without the aid of wisdom, it has considerable weight; but wisdom without justice is of no avail to inspire confidence; for take from a man his reputation for probity, and the more shrewd and clever he is, the more hated and mistrusted he becomes. Therefore, justice combined with practical wisdom will command all the confidence we can desire; justice without wisdom will be able to do much; wisdom without justice will be of no avail at all. {35} X.
But I am afraid someone may wonder why I am now separating the virtues — as if it were possible for anyone to be just who is not at the same time wise; for it is agreed upon among all philosophers, and I myself have often argued, that he who has one virtue has them all.” source