Note 14 — THE AMERICAN SCHOLAR.
Reading edition
Know thyself. Plutarch ascribes this saying to Plato. It is also ascribed to Pythagoras, Chilo, Thales, Cleobulus, Bias, and Socrates; also to Phemonië, a mythical Greek poetess of the ante-Homeric period. Juvenal (Satire XI. 27) says that this precept descended from heaven. "Know thyself" and "Nothing too much" were inscribed upon the Delphic oracle.
"Know then thyself, presume not God to scan; The proper study of mankind is man."