The abuse of the physical frame by the young and seemingly immortal is a folly to be warned against but not prevented, a folly for which the pains of premature decrepitude are the just tax; whereas a youth spent cultivating the delights of study pays rich dividends as the years roll on. For, as Holbrook Jackson (The Anatomy of Bibliomania, 121 f.) maintains:
No labour in the world is like unto study, for no other labour is less dependent upon the rise and fall of bodily condition; and, although learning is not quickly got, there are ripe wits and scholarly capacities among men of all physical degrees, whilst for those of advancing years study is of unsurpassed advantage, both for enjoyment and as a preventative of mental decay. Old men retain their intellects well enough, said Cicero, then on the full tide of his own vigorous old age, if only they keep their minds active and fully employed; [De Senectate, 22, tr. E. S. Shuckburgh, 38] and Dr. Johnson holds the same opinion: There must be a diseased mind, he said, where there is a failure of memory at seventy. [Life, ed. Hill, iii, 191] Cato (so Cicero tells us) was a tireless student in old age; when past sixty he composed the seventh book of his Origins, collected and revised his speeches, wrote a treatise on augural, pontifical, and civil law, and studied Greek to keep his memory in working order; he held that such studies were the training grounds of the mind, and prophylactics against consciousness of old age. [Op. cit. 61-62]
The indefatigable Mr. Jackson continues in this vein for another closely printed page, most interestingly, but most taxingly for your humble transcriber. I must now quit the scriptorium and the 'sphere to sally forth in quest of vittles for the evening's repast.