Yayati is cursed with premature old age by Shukracharya, guru to the demons, as punishment for infidelity to Shukracharya’s own daughter Devayani, Yayati’s wife. The curse strikes instantly and completely, transforming a king in the prime of his life into an old man overnight, and Yayati, unwilling to accept an existence stripped of youth’s pleasures before he has finished indulging in them, negotiates a single concession from Shukracharya: the curse can be transferred to anyone willing to exchange their own youth for his old age, for a period of one thousand years, after which the borrowed youth returns and the exchange reverses.
Yayati asks each of his five sons in turn to make this exchange, offering his own kingdom in return for their youth, and four of them, Yadu, Turvasu, Druhyu and Anu, refuse outright, unwilling to trade away their own vital years so their father can continue pursuing pleasures most people are expected to set aside with age. Only Puru, the youngest, agrees, taking on his father’s decrepitude and handing over his own youth without argument, an act the text frames explicitly as filial devotion overriding any calculation of personal cost, comparable in its unconditional quality to Shravan Kumar’s service elsewhere in the tradition’s store of stories.
Yayati spends a thousand years in Puru’s borrowed body pursuing every pleasure available to him without restraint, and at the end of that period arrives at a realization the epic states directly rather than leaving implicit: desire is not satisfied by being fed. It only grows sharper and more insistent with every indulgence granted it, like a fire that consumes more fuel the more it is fed rather than less, and a thousand years of unlimited gratification has left him no closer to contentment than the single night the curse first struck. He returns Puru’s youth immediately, blesses him with the kingdom in place of the elder sons who had refused the exchange, and retires to the forest to pursue the very renunciation he had spent a millennium delaying.
The tradition keeps this story as one of its sharper statements against the assumption that desire can be managed by satisfying it thoroughly enough, an assumption the modern world tests as readily as Yayati did with a full millennium at his disposal. What the story adds beyond that lesson is the cost borne by someone other than the one learning it: Puru’s youth spent standing in for his father’s indulgence, an entire life’s most vital years handed over not for any wrong Puru committed but purely so his father could keep testing a hypothesis about pleasure that experience alone, eventually and only after everything else had been tried, finally disproved.
Part 24 of 30 — Series IV: Thus It Was