Knowledge (ordinarily) acquired in younger days becomes weakened with decrepitude. Through the good effects of past lives, a person, however, of ripe understanding succeeds in killing his desires.
तरुणाधिगतं ज्ञानं जरादुर्बलतां गतम्। विपक्वबुद्धिः कालेन आदत्ते मानसं बलम्॥