Full Idea
Education does not take root in the soul unless one goes deep.
Gist of Idea
Successful education must go deep into the soul
Source
Protagoras (fragments/reports [c.441 BCE], B11), quoted by Plutarch - On Practice 178.25
Book Reference
'Ancilla to the Pre-Socratic Philosophers', ed/tr. Freeman,Kathleen [Harvard 1957], p.127