THE MOST RECENT literary exploration of the dream of philosophia perennis, Gabi Gleichmann's novel The Elixir of Immortality, culminates in a firm conviction: life without end in “this world” would be worth aspiring to and attainable not in the form of an unlimited extension of the normal life span (which Gleichmann, unlike all other authors discussed in this book, does not even try to imagine). Only in the form of living sustained by the memory of generations past and the confidence of living on in the memory of generations to come would immortality be thinkable, possible, and desirable. Passed on from generation to generation, such memory would amount to nothing less than the very idea of culture, protected against the onslaught of transitoriness and oblivion and forever stimulating us to re-think the examined life.

This culture is Janus-faced. As we look back to the generations before us, the past becomes present; what we make of ourselves takes shape in the light of our thoughtful—and critical—remembrance of what we were. But it is not only the look back that helps us understand who we are. Our eyes are also opened to the human condition as we look ahead to what we might be and what not a few of us hope to be in our uncharted future. Such eye-opening is attempted in the excursions of what Borges called “reasoned imagination” into the counterfactual world of immortality: speculative and creative expeditions into an alternative realm beyond the finiteness that is the sine qua non of our lives. Such expeditions are indebted to “the classic philosophical method of counterfactual thought experiments,” as the American philosopher Thomas Nagel formulated it: “To understand the significance of something, imagine its absence and see what else changes.”

One of the more recent of such imaginative explorations of the surreal world of immortality on earth was undertaken in 2005 by the Portuguese Nobel Prize winner José Saramago in his novel As Intermitências da Morte (Death at Intervals, 2008; see above, pp. 152–57). What could have persuaded the author best known for his political and social criticism of the realities of the contemporary scene to turn to the counterfactual theme of life without end? It was his hope to reduce the risk of no longer “know[ing] … what it means to be human” (as the epigraph has it).