The KJV brings out a question that the NASB tries to answer. In the KJV it is not clear who is raging, laughing or resting.
(Proverbs 29:9 NAS77) When a wise man has a controversy with a foolish man, The foolish man either rages or laughs, and there is no rest.In the NASB it seems to be saying that the fool rages and laughs while there is not rest for any. I think the vagueness of the KJV is more accurate.
It would seem that the wise man is just as confounded as the foolish man. The fool because it is his nature, the wise because he wants to help and is rebuffed. It brings to mind one of those sayings that is attributed to the Chinese,
“Any fool can ask a question that a wise man cannot answer.”One of the requirements for a good answer is having it desired and accepted.
So? Keep in mind that this applies to us when we are the fools. How many times has God tried to show us an answer and we reject it because it is not what we want to hear? I know it happens to me.