(Doctrine of Eternal Recurrence — INTRODUCTION, aph. 3)

Yet since this book is addressed, first and foremost, to those free spirits who still carry within themselves that never-sufficiently-mourned spirit of Enlightenment—the spirit that seeks to dispel the “post-structuralist darkness” that has come to dominate the “spaces of thought” after—may we now say it—an unreflective deconstruction of the very elements of thinking and their reduction to the level of a mere “language game,” beyond the anti-deconstructionist search for a new ontology, a “saviour of the mind” (Žižek, Sex and the Failed Absolute, 2019)—the same question must be put to them as well: why, O heirs of Enlightenment, leaders of today’s progressive human thought, do you not believe in the Eternal Return?

Why should the rational incomprehensibility of the mechanism of the Eternal Return constitute an obstacle to your interest in this hypothesis—if not even to its acceptance—especially given that, through the theories arrived at by twentieth-century physics—the theory of relativity and quantum theory—you have already come to realise that this world is, in itself and in all likelihood, rationally incomprehensible? Both theories, and quantum theory in particular (together with its wholly rationally incomprehensible Copenhagen interpretation), are not rationally intelligible in the way scientific theories of earlier centuries once were. Common sense cannot grasp them. We know how they work and function, but we do not know why they work as they do; and least of all—at least for the time being—do we understand why they mutually exclude one another. What we observe, then, is that in much the same way the rational incomprehensibility of the hypothesis of the Eternal Return should not, from the outset, repel you—as it evidently does. It should not prevent you from engaging with it more seriously, for you have already trained your mind to endure the rational incomprehensibility of the world that surrounds you.

What, then, is the true reason for your disbelief in the Eternal Return? Does it stem from calculations of the “heat death” of the universe, once regarded as its sole ultimate fate? Hardly—for you yourselves are no longer so convinced of the inevitability of the universe’s heat death. In the meantime, other scenarios have emerged that predict markedly different destinies for the cosmos, some of which partially—or at least to some extent—set the stage for a cosmological account of the mechanism of the Eternal Return. One of them, known as the big bounce, goes so far as to almost entirely prepare the stage for the “enactment” of the Eternal Return, which unfolds in so-called “bounces,” through cycles of contraction and expansion and of a cosmic hylē—unknown to us—from which this universe is composed; another scenario, by contrast, claims that the universe will end in a big crunch. Both scenarios, whether or not they are explicitly connected to the Eternal Return, agree at least on one point: they stand in direct opposition to the image of the universe’s “heat death”—alongside which contemporary cosmology considers other possibilities as well.

Thus, it would seem that the true reason for your disbelief in the doctrine of the Eternal Return lies neither in its rational incomprehensibility nor in the personal, existential unbearability of this thought, but in something else—something upon which we have already passed judgment in the Preface. What first repels you from this thought—so we wrote—“does not lie in the [rational incomprehensibility and] unbearability of the eternal return of one’s own suffering and pain, but in the unbearability of witnessing the suffering and pain of others—in the sheer horror that arises from it.” Who could endure that? The certainty of an unpleasant companion of all existence in this world—suffering—once compelled even a Buddha to begin teaching the extinction of all sensations, in order to avoid it. To this objection against the call to accept the doctrine of the Eternal Return, it is indeed difficult to respond. It seems that for many, precisely for this reason, insight into this doctrine must remain withheld.

Apart from Nietzsche, this is the question we ourselves pursued the longest—the question that “in the most dreadful nights touched us most deeply and pressed upon us most gloomily”; the question because of which there will always be those among you who will reject this teaching from the very outset. Yet in that same Preface we already dared to offer an answer to it—“an answer that [may] require centuries to be understood, and then accepted”—and it does no harm to repeat it once more here, for it appears decisive; after all, we shall return to it throughout the entire book.

For what must be regarded as the greatest value in our life—a life that returns—are not our judgments about ourselves, the world, and others, for these are the greatest illusions, but the moments of happiness, fulfilment, and inner serenity that arise within us and that, as such, eternally return. Who are we? What is this world? We cannot know that. We can know only what we do, what we desire, and what we do not wish to do—and how we feel while doing so. And if we focus our thoughts on those moments in which we felt happy, fulfilled, and serene, then perhaps we may be able to endure the thought of the Eternal Return. And so we conclude this aphorism with the same passage as the one to which we referred in the Preface:

“Nietzsche wrote that the ability to endure the thought of the Eternal Return depends on whether one has experienced at least a single such moment—one that one would wish to experience again. A person who has lived through even one such moment is prepared to endure the thought of the Eternal Return.”