The heart of him that hath understanding seeketh knowledge (Proverbs 18:15). The wise man knows that he knows nothing, and is always seeking to learn more.
σοφία γάρ ἐστι καὶ μαθεῖν ὂ μὴ νοεῖς
"To learn what thou hast never thought is wisdom."
The mouth of fools. Another reading, is "the face of fools;" but the former is more suitable to what follows. Feedeth on foolishness. So the Vulgate and Septuagint, "The mouth of the undisciplined knoweth evil." The fool is always gaping and devouring every silly, or slanderous, or wicked word that comes in his way, and in his turn utters and disseminates it.