Yes, Plutarch wrote an essay called “To the Educated Ruler”. And it has no relevance today, at all. Really, read to the end of this passage (780a-c)…
“The majority of kings and rulers are stupid–they imitate those artless sculptors who believe that their oversized figures seem large and solid if they make them with a wide stance, flexing their muscles, mouths gaped open. For these types of rulers seem merely to be imitating the impressiveness and seriousness of leadership with their deep voice, severe glance, bitter manners and their separate way of living: but they are not really any different from the sculpted colossus which is heroic and godly on the outside, but filled with dirt, stone or lead within.
The real difference is that the weight of the statue keeps it standing straight, never leaning; these untaught generals and leaders often wobble and overturn because of their native ignorance. For, because they have built their homes on a crooked foundation, they lean and slide with it. Just as a carpenter’s square, if it is straight and solid, straightens out everything else that is measured according to it, so too a leader must first master himself and correct his own character and only then try to guide his people. For one who is falling cannot lift others; one who is ignorant cannot teach; one who is simple cannot manage complicated affairs; one who is disordered cannot create order; and one who does not rule himself cannot rule.”
Ἀλλὰ νοῦν οὐκ ἔχοντες οἱ πολλοὶ τῶν βασιλέων καὶ ἀρχόντων μιμοῦνται τοὺς ἀτέχνους ἀνδριαντοποιούς, οἳ νομίζουσι μεγάλους καὶ ἁδροὺς φαίνεσθαι τοὺς κολοσσούς, ἂν διαβεβηκότας σφόδρα καὶ διατεταμένους καὶ κεχηνότας πλάσωσι· καὶ γὰρ οὗτοι βαρύτητι φωνῆς καὶ βλέμματος τραχύτητι καὶ δυσκολίᾳ τρόπων καὶ ἀμιξίᾳ διαίτης ὄγκον ἡγεμονίας καὶ σεμνότητα μιμεῖσθαι δοκοῦσιν, οὐδ᾿ ὁτιοῦν τῶν κολοσσικῶν διαφέροντες ἀνδριάντων, οἳ τὴν ἔξωθεν ἡρωικὴν καὶ θεοπρεπῆ μορφὴν ἔχοντες ἐντός εἰσι γῆς μεστοὶ καὶ λίθου καὶ μολίβδου· πλὴν ὅτι τῶν μὲν ἀνδριάντων ταῦτα τὰ βάρη τὴν ὀρθότητα μόνιμον καὶ ἀκλινῆ διαφυλάττει, οἱ δ᾿ ἀπαίδευτοι στρατηγοὶ καὶ ἡγεμόνες ὑπὸ τῆς ἐντὸς ἀγνωμοσύνης πολλάκις σαλεύονται καὶ περιτρέπονται· βάσει γὰρ οὐ κειμένῃ πρὸς ὀρθὰς ἐξουσίαν ἐποικοδομοῦντες ὑψηλὴν συναπονεύουσι. δεῖ δέ, ὥσπερ ὁ κανὼν αὐτός, ἀστραβὴς γενόμενος καὶ ἀδιάστροφος, οὕτως ἀπευθύνει τὰ λοιπὰ τῇ πρὸς αὑτὸν ἐφαρμογῇ καὶ παραθέσει συνεξομοιῶν, παραπλησίως τὸν ἄρχοντα πρῶτον τὴν ἀρχὴν κτησάμενον ἐν ἑαυτῷ καὶ κατευθύναντα τὴν ψυχὴν καὶ καταστησάμενον τὸ ἦθος οὕτω συναρμόττειν τὸ ὑπήκοον· οὔτε γὰρ πίπτοντός ἐστιν ὀρθοῦν οὔτε διδάσκειν ἀγνοοῦντος οὔτε κοσμεῖν ἀκοσμοῦντος ἢ τάττειν ἀτακτοῦντος ἢ ἄρχειν μὴ ἀρχομένου·
[If you are interested in ancient Greek and Roman reflections on leadership, check out this virtual conference going live next week: Teaching Leaders and Leadership Through Classics]