Seneca the Elder, Controversiae
1 pr. 2 (tr. M. Winterbottom):
But by now old age has made me regret the loss of many of my faculties. It has dimmed my eyesight, dulled my hearing, made my strong muscles tired: but among these things I mention it is memory, of all parts of the mind the most vulnerable and fragile, that old age first assaults.
sed cum multa iam mihi ex me desideranda senectus fecerit, oculorum aciem retuderit, aurium sensum hebetaverit, nervorum firmitatem fatigaverit, inter ea quae rettuli memoria est, res ex omnibus animi partibus maxime delicata et fragilis, in quam primam senectus incurrit.