Proverbs 12:23 Kabbalah

אָדָ֣ם עָ֭רוּם כֹּ֣סֶה דָּ֑עַת וְלֵ֥ב כְּ֝סִילִ֗ים יִקְרָ֥א אִוֶּֽלֶת׃

A prudent man concealeth knowledge; But the heart of fools proclaimeth foolishness.

Read kabbalistic (mystical) interpretation of Proverbs 12:23: and classical mystical sources.