Not ONLY fools are beyond reproach but...

The choice between wisdom and folly is directly tied to our response to correction and instruction. The scoffer always finds an excuse for ignoring correction, but the wise man loves reproof.

Discussion, questions?

I don't know about loving reproof, but at least being willing to accept it.
I would think that there are wise people around who don't dwell in the past and think in a forwards manner. So they don't stick around waiting for someone to correct them, but go about seeking their own correction and education.

Wisdom is gained by experience, not from books or teachers. Those can only provide guide posts pointing the way. It is up to the individual to learn from their mistakes and to move forward, because to avoid the lessons that life has to offer is to stagnate, to be condemned to repeat the same circumstance over and over until the lesson is learned. Wisdom or folly is a judgment based on what? Something some one told you or something you read? I don't think life works like that.