Κοιναὶ ἔννοιαι

[Note] that if thought at some time argues about the intelligible objects, [it does so] not by itself, but being joined with the intellect, just as it also argues about the sensible objects being joined with imagination. For even though¹ most of us do not take part in this intellect, however, certain traces and appearances have reached us. These things are the common conceptions that go through everything, [and] they clearly are appearances of the intellect.
This is why they also say that intellect is the principle of knowledge, that with which we know the intelligible objects.
[Note] that the rational soul contains the essential rational accounts of things in itself, since it has descended into matter, as if it were buried in it, just like a spark hidden in the ashes.
Now, just as when someone digs up the ashes a little, the spark immediately shines again, but the person digging did not make the spark. In the same way the opinion, stimulated through the agency of sensation, emits rational accounts of the existing things. Thus they also maintain that teachers do not put knowledge in us, but reveal the [knowledge] which is present in us and, in a way, hidden. And these are the common conceptions, the shadows of intellect. For everything we know more powerfully than [what is perceived] by demonstration, these we know in accordance with a common conception. But the conclusions of these things that require a proof to be known are the function of opinion to know without demonstration.