as we know that man has intellectual powers, because we see what he does, and in no other way do we know it.
 Marcus Aurelius, Meditations (c. 170 - 180). copy citation

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Author Marcus Aurelius
Source Meditations
Topic power
Date c. 170 - 180
Language English
Reference
Note Translated by George Long
Weblink https://www.gutenberg.org/files/15877/15877-h/15877-h.htm

Context

“It is supposed that this may be explained by the Stoic doctrine, that the universe is a god or living being (iv. 40) , and that the celestial bodies are gods (viii. 19) . But the emperor may mean that we know that the gods exist, as he afterwards states it, because we see what they do; as we know that man has intellectual powers, because we see what he does, and in no other way do we know it. This passage then will agree with the passage in the Epistle to the Romans (i. v. 20) , and with the Epistle to the Colossians (i. v. 15) , in which Jesus Christ is named "the image of the invisible god;"” source