For Nietzsche, The Birth of Tragedy (BoT) was an account of how the Greeks were able to overcome their pessimism; how they were able to, via tragedy, affirm life despite knowing the “terror and horror of existence” (42). Throughout Nietzsche’s discussion, the language he uses suggests a metaphysical basis to his claims. For example, his talk involves: a primal unity of being, which is (paradoxically, it seems) marked by eternal contradiction; an Apollonian impulse to attain redemption through illusion, the “mere appearance of mere appearance” (45); and a Dionysian impulse that shatters individuality, effecting the “union between man and man is reaffirmed” wherein humanity is reconciled with the unity nature (37). Thus, accepting Nietzsche’s argument regarding the possibility of offering an earnest “Yes” to life also seems to entail accepting the demand of maintaining “Yes” to a metaphysical theory—one that is appears at best puzzling, or at worst naively underdeveloped. But does the text actually require this of its readers? If not, is some other form of metaphysics implied?
It is often said that Nietzsche later came to reject his early reliance on metaphysics. If this is the case, then perhaps readers ought to read BoT merely in order to grasp the broad themes of Nietzsche’s philosophy. That is, one approach could be to read BoT in order to see, in raw form, the shape of a young intellectual’s prowess—as he artistically juggles difficult metaphysical positions—but not in order to attain a deeper picture of the substratum of his thought. There is certainly much to gain from this sort of reading. One gleans, for instance, the budding of Nietzsche’s powerful genealogical approach to cultural-historical critique. But despite admitting many interesting elements of BoT, this approach seems to run contrary to the view of the text that Nietzsche had later in life. In his reflection in Ecce Homo, Nietzsche still happily asserts that he has “the right to understand [himself] as the first tragic philosopher” (729). With this comment, Nietzsche means to highlight that his work has remained antipodal to pessimism: he has been steadfast in his yearning for life-affirmation. But that cannot be all that Nietzsche is saying; in his Ecce Homo discussion, he praises the profundity of BoT’s philosophical innovations; the Apollonian and Dionysian; the importance of positively affirming the truth of reality, rather than turning “against life with subterranean vengefulness” (728). Thus, Nietzsche must still carry with him something more than just the broad themes of the text and his fierce acumen.
Yet even still, Nietzsche did find the metaphysics guiding BoT problematic. He tells us so: his problem was that the text “smelled offensively Hegelian” (726). What does he mean by this? Moreover, what metaphysical presuppositions could be rejected from BoT without also inevitably abandoning the Apollonian, the Dionysian, and the truth of reality, etc.? What Nietzsche is saying, it seems, is that he is not necessarily dissatisfied with his view of the chaos of life, or the “real truth of nature”; rather, the problem has to do with the dialectical shape of his vision. That is, what Nietzsche finds so offensive in the metaphysics of BoT is (a) that two antithetical impulses merge to produce unity, and (b) that history is the development of that idea. With this in mind, it becomes much easier to locate the dialectic that Nietzsche later found reeking of metaphysics.
First there is an original contradiction. In BoT conflict is introduced between, for example, individuation/primal unity, and life/suffering, and between will/appearance. Nietzsche’s goal, therefore, when he talks about the Greek’s redemption, is illustrating the way that the original contradiction can be justified and redeemed in some kind of resolution or unity. Second, the Apollonian and the Dionysian, as rudimentary impulses of nature, serve as modes through which the contradiction is reflected. But as Nietzsche’s story unfolds, the reader soon finds that these impulses are not in a relation that ends eternally in contradiction; instead, Nietzsche reveals, the Apollonian and Dionysian are antithetical means of resolving the contradiction. In Nieztsche’s own words:
I see Apollo as the transfiguring genius of the principium individuationis through which alone the redemption in illusion is truly to be obtained; while by the mystical triumphant cry of Dionysus the spell of individuation is broken, and the way lies open to the Mothers of Being, to the innermost heart of things (99).
Thus, third, the Greeks manifest humanity’s reconciliation with the terror of existence in and through the synthesizing of the antithetical approaches to understanding the depth of life. “Yes,” Dionysus: yours is the essence of tragic wisdom, the intoxicating chorus in which the suffering of individuation dissolving blissfully into primal Being. “Yes,” Apollo: yours is the essence of tragedy’s drama, the world of images in which superficiality can be made to stand in for depth. Together, these opposing affirmations realize the creative genius of tragedy. Nietzsche writes, “we must understand the Greek tragedy as the Dionysian chorus which ever anew discharges itself in an Apollinian world of images…the drama is the Dionysian embodiment of Dionysian insight and effects” (65). In affirming an antithesis, the Greeks learned to meet the original contradiction of nature, harnessing the aesthetic impulses that reflected such contradiction. Here, in the objectification of the Dionysian in the world of Apollonian images, the contradictory ground of being has finally found its unity.
This picture is one of awe. Yet, Nietzsche came to see it as an image of decay (729). Perhaps he was later glad to have come to realize that a deeper set of background assumptions conditioned his historical interpretation of tragedy. That way, he could learn to throw off Hegelian metaphysics—which Nietzsche would surely want to critique as being Socratic or Christian (or both?), and therefore nihilistic—and develop a form of historical critique in its stead. Nietzsche’s dissatisfaction with the Hegelian metaphysic, it seems, was that it assumed unity to be fundamentally primary; thereby only provided a picture of how to affirm the unity-in-contradiction of life. Be criticizes it, therefore, because it was not sufficient for him to affirm “passing away and destroying”, “opposition and war”, or becoming rather than being (729). Perhaps Nietzsche, contra Hegel (and perhaps all of the philosophical tradition that came before), was not after unity-in-contradiction; but instead, hoping to affirm the contradiction-in-unity that he saw as the very heart of unity-in-contradiction: the contradiction inhabiting nature.
But I have now reached, once more, the impasse with which we began: does accepting Nietzsche’s “Yes” to life entail maintaining a “Yes” to a metaphysical theory?
 Parenthetical citations refer to pagination in the Basic Writings of Nietzsche collection.