Lost Youth in Different Periods And Timelines

At the ends of their respective sub-series of Poul Anderson's Technic History, Chee Lan and Miriam Abrams make essentislly the same remark: their youth is gone. See here. There are other literary echoes. Chee Lan's shipmate, Adzel, says that those were good years just as Agatha Christie's Hercule Poirot says that those were good days. We remember and agree. Anderson's Manse Everard cannot recapture the experience of his boyhood before the war even though he is a time traveller! He can, of corse, space-time travel to the Midwest pre-1942... but he is not the same, as Chee Lan says.

This experience is common to all of literature. Poul Anderson expresses it in science fiction.

"Bid time return..."