Cicero, de Officiis 3.1:
“My dear son Marcus, Cato once wrote that his rough contemporary Publius Scipio, the one who first earned the appellation of Africanus, was accustomed to say that he was never less at his leisure than in his leisure hours, nor less alone than when he was by himself. This is a magnificent saying, truly worthy of a great and wise man. It shows that he thought about work even in his free time, and was accustomed to speak with himself even in solitude, so that he would never cease working and would not want for the conversation of another now and then. And so these two things – leisure and solitude – which tend to generate a certain feebleness in others, had the effect of sharpening him. I would wish that this could be said truly even of us, but if we are less able to follow such great excellence of intellect by imitation, perhaps we can get close to it through an effort of will. For you see, having been prohibited from government and business in the forum by criminal arms and violence, I am here at my leisure and on that account, I have left the city behind and often wander through the fields alone.”
P. Scipionem, Marce fili, eum, qui primus Africanus appellatus est, dicere solitum scripsit Cato, qui fuit eius fere aequalis, numquam se minus otiosum esse, quam cum otiosus, nec minus solum, quam cum solus esset. Magnifica vero vox et magno viro ac sapiente digna; quae declarat illum et in otio de negotiis cogitare et in solitudine secum loqui solitum, ut neque cessaret umquam et interdum conloquio alterius non egeret. Ita duae res, quae languorem adferunt ceteris, illum acuebant, otium et solitudo. Vellem nobis hoc idem vere dicere liceret, sed si minus imitatione tantam ingenii praestantiam consequi possumus, voluntate certe proxime accedimus. Nam et a re publica forensibusque negotiis armis impiis vique prohibiti otium persequimur et ob eam causam urbe relicta rura peragrantes saepe soli sumus.