"Dr. Heidegger's Experiment" by Nathaniel Hawthorne is a story about the consistency of human nature. The rather mystical old doctor has procured, he claims, water which will make people young. He gathers four of his old friends to help him test the water. What he is really testing, of course, is whether age and experience have taught his friends anything. If it has, when they get younger they will not revert to the same  behaviors and patterns from the past; if they have not, they will revert to their old vices and habits.

Among the four friends are three men and a woman, Widow Wycherly. Each of them is suffering, in their old age, the effects of the problems they each dealt with in their lives. One of the men is Colonel Killigrew, and the narrator tells us this about him:

Colonel Killigrew had wasted his best years, and his health and substance, in the pursuit of sinful pleasures, which had given birth to a brood of pains, such as the gout, and divers other torments of soul and body.

Clearly he was once a young man who was excessive in his eating and drinking, among other pleasures, and these have ruined his body. All three men were once in love with the Widow Wycherly, and Colonel Killigrew's approach was to use false flattery to capture her attention. The three men fought each other for her once, but obviously she chose none of them.

The doctor's "foul guests" do not believe him, but they want to. They each have questions about what the elixir can do for them.

"Ahem!" said Colonel Killigrew, who believed not a word of the doctor's story; "and what may be the effect of this fluid on the human frame?"

Despite their disbelief, all four of them drink the water. When they begin to see some changes, they demand more, and the doctor obliges. Eventually the four old friends are young again, and all of them, unfortunately, revert to their old ways. Colonel Killigrew wants the widow to dance with him, and he pays her compliments which are "not always measured by sober truth." Soon he is singing drunkenly and raucously as he watches the widow lasciviously.

Sadly, these four people have learned nothing from their life experiences; however, Doctor Heiddegger's experiment was successful.