Plutarch An seni respublica gerenda sit 23

[23] But more statesmanlike than this it is, not merely to avoid, when rebuking them openly and in public, any biting speech which violently represses and humiliates them, but rather in kindly spirit to suggest and inculcate in private to those who have natural ability for public affairs advantageous words and policies, urging them on towards that which is noble, adding brilliancy to their minds, and, after the manner of riding-teachers, enabling them at first to mount the populace when it is tractable and gentle; then, if the young man fails in any way, not letting him be discouraged, but setting him on his feet and encouraging him, as Aristeides raised up and encouraged Cimon and Mnesiphilus did the like for Themistocles when they were at first disliked and decried in the city as being rash and unrestrained. And there is also a story that when Demosthenes had met with a reverse in the assembly and was disheartened thereby, an aged man who had formerly heard Pericles speak touched him with his hand and told him that he resembled that great man in natural ability and, therefore, had been unjust in condemning himself. And so also when Timotheüs was hissed for being new-fangled and was said to be committing sacrilege upon music, Euripides told him to be of good courage, for in a little while the theatres would be at his feet.

[23] And it were yet more civil and politic, not only in reprehending them openly and in the face of the people, to forbear that sharpness of speech which exceedingly dashes a young man and puts him out of countenance, but rather, wholly abstaining from all such public reproofs, privately to instruct such as have a good genius for the managing of state affairs, drawing them on by setting gently before them useful counsels and political precepts, inciting them to commendable actions, enlightening their understanding, and showing them, as those do who teach to ride, how at their beginning to render the people tractable and mild, and if any young man chances to fall, not to suffer him to lie gasping and panting on the ground, but to help him up and comfort him, as Aristides dealt by Cimon, and Mnesiphilus by Themistocles; whom they raised up and encouraged, though at first they were harshly received and ill spoken of in the city, as audacious and intemperate. It is said also, that Demosthenes being rejected by the people and taking it to heart, there came to him a certain old man, who had in former years been an hearer of Pericles, and told him, that he naturally resembled that great man, and did unjustly cast down himself. In like manner Euripides exhorted Timotheus, when he was hissed at for introducing of novelty, and thought to transgress against the law of music, to be of good courage, for that he should in a short time have all the theatres subject to him.