If we affirm one moment, we thus affirm not only ourselves but all existence. For nothing is self-sufficient, neither in us ourselves nor in things; and if our soul has trembled with happiness and sounded like a harp string just once, all eternity was needed to produce this one event - and in this single moment of affirmation all eternity was called good, redeemed, justified, and affirmed.
Derridean interpretation 
Jacques Derrida allocates this concept and applies it specifically to language, its structure and play. This application acknowledges that there is, in fact, no center or origin within language and its many parts, no firm ground from which to base any Truth or truths. This shock allows for two reactions in Derrida’s philosophy: the more negative, melancholic response, which he designates as Rousseauistic, or the more positive Nietzschean affirmation. Rousseau's perspective focuses on deciphering the truth and origin of language and its many signs, an often exhaustive occupation. Derrida's response to Nietzsche, however, offers an active participation with these signs and arrives at, in Derridean philosophy, a more resolute response to language.
In “Structure, Sign, and Play”, Derrida articulates Nietzsche’s perspective as
…the joyous affirmation of the play of the world and of the innocence of becoming, the affirmation of a world of signs without fault, without truth, and without origin which is offered to an active interpretation.
Essentially, Derrida not only fosters Nietzsche’s work but evolves it within the sphere of language; in doing so, Derrida acquires and employs Nietzsche’s optimism in his concept of play: "the substitution of given and existing, present, pieces" (292). Much of this spirit resides in the abandonment of any sort of new humanism. This acceptance of the inevitable allows for considerable relief — evident in the designation of the loss of center as a noncenter — as well as the opportunity to affirm and cultivate play, which enables humanity and the humanities “to pass beyond man and humanism” (292).
Contra Schopenhauer 
Walter Kaufmann wrote that Nietzsche “celebrates the Greeks who, facing up to the terrors of nature and history, did not seek refuge in ‘a Buddhistic negation of the will,’ as Schopenhauer did, but instead created tragedies in which life is affirmed as beautiful in spite of everything.” Schopenhauer’s negation of the will was a saying “no” to life and to the world, which he judged to be a scene of pain and evil. “[D]irectly against Schopenhauer’s place as the ultimate nay–sayer to life, Nietzsche positioned himself as the ultimate yes–sayer….” Nietzsche’s affirmation of life's pain and evil, in opposition to Schopenhauer, resulted from an overflow of life. Schopenhauer’s advocacy of self–denial and negation of life was, according to Nietzsche, very harmful. For his entire mature life, Nietzsche was concerned with the damage that he thought resulted from Schopenhauerian disgust with life and turning against the world..
See also 
- Derrida, Jacques. “Structure, Sign, and Play in the Discourse of the Humanities.” Writing and Difference. Trans. Alan Bass. Chicago: U of Chicago P, 1978. 278-293.
- Encyclopedia of Philosophy, “Friedrich Nietzsche,” vol. 5, Macmillan, New York, 1967, Page 507.
- A Companion to Schopenhauer, edited by Bart Vandenabeele, Part IV, ch. 19, article by Ken Gemes and Christopher Janaway, “Life–Denial versus Life–Affirmation: Schopenhauer and Nietzsche on Pessimism and Asceticism,” Blackwell, New York, 2012, Page 289
- “I was the first to see the actual contrast: the degenerate instinct which turns upon life with a subterranean lust of vengeance (Christianity, Schopenhauer's philosophy, and in some respects too even Plato's philosophy — in short, the whole of idealism in its typical forms), as opposed to a formula of the highest yea-saying to life, born of an abundance and a superabundance of life — a yea-saying free from all reserve, applying even to suffering, and guilt, and all that is questionable and strange in existence.” (Nietzsche, On the Genealogy of Morality, Preface, § 5)
- “For me the issue was the value of morality—and in that matter I had to take issue almost alone with my great teacher Schopenhauer…. The most specific issue was the worth of the 'unegoistic,' the instinct for pity, self-denial, self-sacrifice, something which Schopenhauer himself had painted with gold, deified, and projected into the next world for so long that it finally remained for him 'value in itself' and the reason why he said No to life and even to himself. But a constantly more fundamental suspicion of these very instincts voiced itself in me, a scepticism which always dug deeper! It was precisely here that I saw the great danger to humanity, its most sublime temptation and seduction.” (Nietzsche, Ecce Homo, “Why I Write Such Good Books,” “The Birth of Tragedy,” § 2.)