matter is not a principle of action, but is the subject that receives the effect of action.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic action principles
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

“and thus operation is the end of the creature. We must therefore understand that God works in things in such a manner that things have their proper operation. In order to make this clear, we must observe that as there are few kinds of causes; matter is not a principle of action, but is the subject that receives the effect of action. On the other hand, the end, the agent, and the form are principles of action, but in a certain order. For the first principle of action is the end which moves the agent; the second is the agent; the third is the form of that which the agent applies to action” source