We ought to give our friend pain if it will benefit him, but not to the extent of breaking off our friendship; but just as we make use of some biting medicine that will save and preserve the life of the patient. And so the friend, like a musician, in bringing about an improvement to what is good and expedient, sometimes slackens the chords, sometimes tightens them, and is often pleasant, but always useful.
PlutarchSometimes small incidents, rather than glorious exploits, give us the best evidence of character. So, as portrait painters are more exact in doing the face, where the character is revealed, than the rest of the body, I must be allowed to give my more particular attention to the marks of the souls of men.
Plutarch