Before Dr. Heidegger has begun to conduct his "experiment" on his elderly acquaintances, the narrator describes them in a series of striking hyperboles that greatly exaggerate their age, even suggesting that they were never young:
They looked as if they had never known what youth or pleasure was, but had been the offspring of Nature’s dotage, and always the gray, decrepit, sapless, miserable creatures, who now sat stooping round the doctor’s table, without life enough in their souls or bodies to be animated even by the prospect of growing young again.
Rather than merely describing these characters as old, the narrator here suggests that they appear to have always been old—they are the "offspring of Nature's dotage," or, in other words, the children born to Nature in its own old age. The reader is encouraged to imagine them, then, as having been born already elderly and to have never experienced the enjoyments of youth. The narrator does not mean that this is literally the case, and the reader in fact learns a good deal about their earlier lives and youthful mistakes. Nevertheless, in exaggerating their age and suggesting that they lack the vitality to even be excited by the prospect of youth, the "transformation" they undergo throughout the course of the story becomes all the more shocking to the reader.