comfort
Explanation
The Joke
An old man has found the Fountain of Youth. The guardian of the fountain offers him the chance to go back to being young, listing all the things that come with youth: "the angry teens, the confused twenties, the anxious thirties, the mid-life crises, the cynical fifties, or the aching sixties." The old man pauses, then admits: "I'd really be more about external than internal youth, right?"
The guardian presses further, asking if the man is ready to give up his accumulated wisdom: no regret, no pain, no fear, no "concern about other people's opinions of me." The old man hesitates. The fountain then clarifies: "Sorry, I should have asked -- you want the Fountain of Beauty?" suggesting that what people actually want when they say they want youth is not the emotional turmoil of being young again, but simply to look young while keeping their hard-won emotional maturity.
The Humor
The comic cleverly deconstructs the universal wish for youth by separating the desire for a youthful appearance from the reality of youthful experience. When forced to actually enumerate what being young entails -- the confusion, anxiety, insecurity, and emotional volatility -- the old man realizes he does not want any of that back. He just wants to look good again. The Fountain of Youth revealing that it should have offered the "Fountain of Beauty" instead is a sharp observation about how nostalgia for youth is really just vanity dressed up as a deeper longing. The comic suggests that most people, given the honest choice, would not trade their emotional maturity for a do-over of their twenties.
References
The Fountain of Youth is a legendary spring said to restore youth to anyone who drinks from it, famously associated with the Spanish explorer Juan Ponce de Leon and his explorations of Florida in the early 16th century.