Seneca, Moral Epistles 115.1-3
“Oh, my Lucilius! I don’t want you to be too anxious about words and composition. I have more important things for you to care about! Seek what to write, not how to write it. And in this thing itself, seek not to write but to feel it, so you may turn what you feel more into your own, as if pressing your seal into it.
When you see that someone’s work is super careful and polished, know well that the mind is no less obsessed with minor details. The great person speaks in a relaxed fashion and securely. Whatever they say, they say with more confidence than worry.
You know too well those young fashy folks, with their shining beards and hair. You never hope for anything strong or solid from them. Rhetoric is the clothing of the mind–if it is cut, dyed, or done up in some way, it implies that there is something insincere, that there’s some problem.
Nimis anxium esse te circa verba et compositionem, mi Lucili, nolo; habeo maiora, quae cures. Quaere, quid scribas, non quemadmodum; et hoc ipsum, non ut scribas, sed ut sentias, ut illa, quae senseris, magis adplices tibi et velut signes. Cuiuscumque orationem videris sollicitam et politam, scito animum quoque non minus esse pusillis occupatum. Magnus ille remissius loquitur et securius; quaecumque dicit, plus habent fiduciae quam curae.
Nosti comptulos iuvenes, barba et coma nitidos, de capsula totos; nihil ab illis speraveris forte, nihil solidum. Oratio cultus animi est: si circumtonsa est et fucata et manu facta, ostendit illum quoque non esse sincerum et habere aliquid fracti.