But simplicity is not a special virtue, since it rectifies the intention, and that is required in every virtue. Therefore neither is truth a special virtue.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic simplicity virtue
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/18755/pg18755-images.html

Context

“. remember how I have walked before Thee in truth, and with a perfect heart." Now one lives aright by any virtue, as follows from the definition of virtue given above (I-II, Q. 55, A. 4). Therefore truth is not a special virtue.
Obj. 4: Further, truth seems to be the same as simplicity, since hypocrisy is opposed to both. But simplicity is not a special virtue, since it rectifies the intention, and that is required in every virtue. Therefore neither is truth a special virtue. On the contrary, It is numbered together with other virtues (Ethic. ii, 7) .
I answer that, The nature of human virtue consists in making a man's deed good. Consequently whenever we find a special aspect of goodness in human acts, it is necessary that man be disposed thereto by a special virtue.” source