Greek proverb: Αὐτὸς ἔφα

Here's a saying from Apostolius, C4.39, with a Latin version from Clavis Homerica. The image is a bust of Pythagoras at Wikipedia. Here are some more Apostolius proverbs.

Αὐτὸς ἔφα.
Ipse dixit.
He himself said it.