Historia Augusta, Hadrian (§14-15):
Hadrian was excessively devoted to poems and literature, and thoroughly read-up on arithmetic, geometry, and paining. He also made a big show of his knowledge of the cithara and of singing. He was excessive in his pleasures, for he even composed many things in verse about his passions. (He wrote love poems.) This same man was most skilled in arms and most knowledgeable about military affairs, and even handled gladiatorial weapons. One and the same man was severe and happy, charming and grave, quick yet delaying, stingy yet liberal, unaffected yet lying, savage yet merciful, and in all things hard to pin down.
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And although he could easily pour forth either verse or prose and was incredibly skilled in all the arts, yet he mocked, despised, and degraded the professors of all of them. He often battled with these professors and philosophers in books or poems which he published in his turn. And a certain Favorinus stopped using a a word that he liked because Hadrian had censured it, and he was able to excite much laughter among his friends who argued that he did wrong in yielding to Hadrian’s opinion about a word which many perfectly fine writers had employed. For Favorinus said, ‘Friends, you are not counseling me well if you do not allow me to believe that the man who has thirty legions is more learned than everyone else.’
Fuit enim poematum et litterarum nimium studiosissimus. Arithmeticae, geometriae, picturae peritissimus. Iam psallendi et cantandi scientiam prae se ferebat. In voluptatibus nimius. Nam et de suis dilectis multa versibus composuit. (amatoria carmina scripsit.) Idem armorum peritissimus et rei militaris scientissimus, gladiatoria quoque arma tractavit. Idem severus laetus, comis gravis, lascivus cunctator, tenax liberalis, <simplex> simulator, saevus clemens et semper in omnibus varius.
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Et quamvis esset oratione et versu promtissimus et in omnibus artibus peritissimus, tamen professores omnium artium semper ut doctior risit, contempsit, obtrivit. Cum his ipsis professoribus et philosophis libris vel carminibus invicem editis saepe certavit. Et Favorinus quidem, cum verbum eius quondam ab Hadriano reprehensum esset atque ille cessisset, arguentibus amicis, quod male cederet, Hadriano de verbo, quod idonei auctores usurpassent, risum iocundissimum movit; ait enim : “non recte suadetis, familiares, qui non patimini me illum doctiorem omnibus credere, qui habet triginta legiones.”