Life in general is not divided into active and contemplative, but the life of man, who derives his species from having an intellect, wherefore the same division applies to intellect and human life.
 Thomas Aquinas, Summa Theologica (1274). copy citation

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Author Thomas Aquinas
Source Summa Theologica
Topic division life
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

“Each thing's proper form that makes it actually to be is properly that thing's principle of operation. Hence to live is, in living things, to be, because living things through having being from their form, act in such and such a way. Reply Obj. 2: Life in general is not divided into active and contemplative, but the life of man, who derives his species from having an intellect, wherefore the same division applies to intellect and human life. Reply Obj. 3: It is true that contemplation enjoys rest from external movements. Nevertheless to contemplate is itself a movement of the intellect, in so far as every operation is described as a movement;” source