Plutarch said this quote

To make no mistakes is not in the power of man, but from their errors and mistakes the wise and good learn wisdom for the future.

~ Plutarch

Silence at the proper season is wisdom, and better than any speech.

~ Plutarch

The mind is not a vessel to be filled, but a fire to be kindled.

~ Plutarch

It is a thing of no great difficulty to raise objections against another man's oration, it is a very easy matter; but to produce a better in it's place is a work extremely troublesome.

~ Plutarch