Knowledge is not the cause of a thing being done, unless through the will.
 Thomas Aquinas, Summa Theologica (1274). copy citation

add
Author Thomas Aquinas
Source Summa Theologica
Topic cause self-knowledge
Date 1274
Language English
Reference
Note Translated by Fathers of the English Dominican Province
Weblink http://www.gutenberg.org/cache/epub/17611/pg17611-images.html

Context

“Therefore in God there are distinguished will in its proper sense, and will as attributed to Him by metaphor. Will in its proper sense is called the will of good pleasure; and will metaphorically taken is the will of expression, inasmuch as the sign itself of will is called will. Reply Obj. 1: Knowledge is not the cause of a thing being done, unless through the will. For we do not put into act what we know, unless we will to do so. Accordingly expression is not attributed to knowledge, but to will. Reply Obj. 2: Expressions of will are called divine wills, not as being signs that God wills anything;” source