A lesson to take away from this story may be the folly of youth. Before the experiment is conducted, Dr. Heidegger implores his subjects to, with their newly restored youth, act with the wisdom of someone who has already endured all of the years of life. His subjects laugh at the idea of even having to be told this—as if they would ever repeat the mistakes that made them so miserable.
However, as soon as their youth is restored, they begin once again to act foolishly, all of the men fighting over the Widow Wycherly. In their youthful ecstasy, they have completely forgotten the woes that will eventually be coming for them again, and they once again consider themselves to be immortal. Dr. Heidegger, who represents some wisdom in this story, would never drink from the fountain of youth. He states, "having had much trouble in growing old, I am in no hurry to grow young again."