Cato the Younger
Plutarch
Plutarch. Plutarch's Lives, Vol. VIII. Perrin, Bernadotte, translator. Cambridge, MA: Harvard University Press; London: William Heinemann Ltd., 1919.
When, accordingly, he came to study, he was sluggish of comprehension and slow, but what he comprehended he held fast in his memory. And this is generally the way of nature: those who are well endowed are more apt to recall things to mind, but those retain things in their memory who acquire them with toil and trouble;[*](Cf. Aristotle, De Mem. i. 1, 2, 24.) for everything they learn becomes branded, as it were, upon their minds.
It would appear, too, that Cato’s reluctance to be persuaded made his learning anything more laborious. For, to learn is simply to allow something to be done to you, and to be quickly persuaded is natural for those who are less able to offer resistance. Therefore young men are more easily persuaded than old men, and sick folk, than those who are well, and, in a word, where the power to raise objections is weakest, the act of submission is easiest.