A prudent man conceals knowledge, But the heart of fools proclaims foolishness (Proverbs 12:23, NKJV). A wise man does not need to tell all that he knows; he can (and will) make use of his knowledge at proper times, in proper places, and to the right people. The fool, on the other hand, speaks from the mouth whatever is in the heart. An unwise person, hearing this, makes use of this information to manipulate the situation and person. RT