Artistic creation depends on a tension between two opposing forces, which Nietzsche terms the “Apollonian” and the “Dionysian.” Apollo is the Greek god of light and reason, and Nietzsche identifies the Apollonian as a life- and form-giving force, characterized by measured restraint and detachment, which reinforces a strong sense of self. Dionysus is the Greek god of wine and music, and Nietzsche identifies the Dionysian as a frenzy of self-forgetting in which the self gives way to a primal unity where individuals are at one with others and with nature. Both the Apollonian and the Dionysian are necessary in the creation of art. Without the Apollonian, the Dionysian lacks the form and structure to make a coherent piece of art, and without the Dionysian, the Apollonian lacks the necessary vitality and passion. Although they are diametrically opposed, they are also intimately intertwined.

Nietzsche suggests that the people of ancient Greece were unusually sensitive and susceptible to suffering and that they refined the Apollonian aspect of their nature to ward off suffering. The primal unity of the Dionysian brings us into direct apprehension of the suffering that lies at the heart of all life. By contrast, the Apollonian is associated with images and dreams, and hence with appearances. Greek art is so beautiful precisely because the Greeks relied on the appearances generated by images and dreams to shield themselves from the reality of suffering. The early, Doric period of Greek art is dull and prim because the Apollonian influence too heavily outweighs the Dionysian.

The Greek tragedies of Aeschylus and Sophocles, which Nietzsche considers to be among humankind’s greatest accomplishments, achieve their sublime effects by taming Dionysian passions by means of the Apollonian. Greek tragedy evolved out of religious rituals featuring a chorus of singers and dancers, and it achieved its distinctive shape when two or more actors stood apart from the chorus as tragic actors. The chorus of a Greek tragedy is not the “ideal spectator,” as some scholars believe, but rather the representation of the primal unity achieved through the Dionysian. By witnessing the fall of a tragic hero, we witness the death of the individual, who is absorbed back into the Dionysian primal unity. Because the Apollonian impulses of the Greek tragedians give form to the Dionysian rituals of music and dance, the death of the hero is not a negative, destructive act but rather a positive, creative affirmation of life through art.

Unfortunately, the golden age of Greek tragedy lasted less than a century and was brought to an end by the combined influence of Euripides and Socrates. Euripides shuns both the primal unity induced by the Dionysian and the dreamlike state induced by the Apollonian, and instead he turns the Greek stage into a platform for morality and rationality. Rather than present tragic heroes, Euripides gives his characters all the foibles of ordinary human beings. In all these respects, Nietzsche sees Socrates’ influence on Euripides. Socrates effectively invented Western rationality, insisting that there must be reasons to justify everything. He interpreted instinct as a lack of insight and wrongdoing as a lack of knowledge. By making the world seem knowable and all truths justifiable, Socrates gave birth to the scientific worldview. Under Socrates’ influence, Greek tragedy was converted into rational conversation, which finds its fullest expression in Plato’s dialogues.

The modern world has inherited Socrates’ rationalistic stance at the expense of losing the artistic impulses related to the Apollonian and the Dionysian. We now see knowledge as worth pursuing for its own sake and believe that all truths can be discovered and explained with enough insight. In essence, the modern, Socratic, rational, scientific worldview treats the world as something under the command of reason rather than something greater than what our rational powers can comprehend. We inhabit a world dominated by words and logic, which can only see the surfaces of things, while shunning the tragic world of music and drama, which cuts to the heart of things. Nietzsche distinguishes three kinds of culture: the Alexandrian, or Socratic; the Hellenic, or artistic; and the Buddhist, or tragic. We belong to an Alexandrian culture that’s bound for self-destruction.

The only way to rescue modern culture from self-destruction is to resuscitate the spirit of tragedy. Nietzsche sees hope in the figure of Richard Wagner, who is the first modern composer to create music that expresses the deepest urges of the human will, unlike most contemporary opera, which reflects the smallness of the modern mind. Wagner’s music was anticipated by Arthur Schopenhauer, who saw music as a universal language that makes sense of experience at a more primary level than concepts, and Immanuel Kant, whose philosophy exposes the limitations of Socratic reasoning. Not coincidentally, Wagner, Schopenhauer, and Kant are all German, and Nietzsche looks to German culture to create a new golden age.

We have no direct understanding of myth anymore, but we always mediate the power of myth through various rationalistic concepts, such as morality, justice, and history. So far, the tremendous influence of Greek culture has done very little to shift our own culture’s opposition to art because we tend to interpret the Greeks according to our own standards and read tragedies as expressions of moral, rational forces rather than expressions of the mythic forces of the Apollonian and the Dionysian. Myth gives us a sense of wonder and a fullness of life that our present culture lacks. Nietzsche urges a return to our deeper selves, which are entwined in myth, music, and tragedy.

Nietzsche’s concept of the Dionysian, which he refines and alters over the course of his career, stands as a pointed counterbalance to the thoroughgoing rationality that is so prominent in most philosophy. In most scholarly investigations, the importance of truth and knowledge are taken as givens, and thinkers trouble themselves only over questions of how best to achieve truth and knowledge. By contrast, Nietzsche questions where this drive for truth and knowledge come from and answers that they are products of a particular, Socratic view of the world. Deeper than this impulse for truth is the Dionysian impulse to give free rein to the passions and to lose oneself in ecstatic frenzy. We cannot properly appreciate or criticize the Dionysian from within a tradition of rationality because the Dionysian stands outside rationality. As much as the civilized world may wish to deny it, the Dionysian is the source of our myths, our passions, and our instincts, none of which are bounded by reason. While the civilizing force of the Apollonian is an essential counterbalance—contrary to some stereotypes of Nietzsche, he is firmly against the complete abandonment of reason and civilization—Nietzsche warns that we lose the deepest and richest aspects of our nature if we reject the Dionysian forces within us.

For Nietzsche, art is not just a form of human activity but is rather the highest expression of the human spirit. The thrust of the book is well expressed in what is perhaps its most famous line, near the end of section 5: “it is only as an aesthetic phenomenon that existence and the world are eternally justified.” One of Nietzsche’s concerns in The Birth of Tragedy is to address the question of the best stance to take toward existence and the world. He criticizes his own age (though his words apply equally to the present day) for being overly rationalistic, for assuming that it is best to treat existence and the world primarily as objects of knowledge. For Nietzsche, this stance makes life meaningless because knowledge and rationality in themselves do nothing to justify existence and the world. Life finds meaning, according to Nietzsche, only through art. Art, music, and tragedy in particular bring us to a deeper level of experience than philosophy and rationality. Existence and the world become meaningful not as objects of knowledge but as artistic experiences. According to Nietzsche, art does not find a role in the larger context of life, but rather life takes on meaning and significance only as it is expressed in art.

By attacking Socrates, Nietzsche effectively attacks the entire tradition of Western philosophy. While a significant group of Greek philosophers predate Socrates, philosophy generally identifies its start as a distinctive discipline in Socrates’ method of doubt, dialogue, and rational inquiry. While Nietzsche acknowledges that Socrates gave birth to a new and distinctive tradition, he is more interested in the tradition that Socrates managed to replace. Greek tragedy as Nietzsche understands it cannot coexist in a world of Socratic rationality. Tragedy gains its strength from exposing the depths that lie beneath our rational surface, whereas Socrates insists that we become fully human only by becoming fully rational. From Socrates onward, philosophy has been the pursuit of wisdom by rational methods. In suggesting that rational methods cannot reach to the depths of human experience, Nietzsche suggests that philosophy is a shallow pursuit. True wisdom is not the kind that can be processed by the thinking mind, according to Nietzsche. We find true wisdom in the Dionysian dissolution of the self that we find in tragedy, myth, and music.

Nietzsche wrote The Birth of Tragedy at a time when he was most heavily under Wagner’s influence. Nietzsche had met Wagner as a young man and was deeply honored when Wagner chose to befriend him. Wagner impressed his own views on life and art on Nietzsche, and The Birth of Tragedy is, in many ways, a philosophical justification for the work Wagner was carrying out in his operas. Over the course of the 1870s, however, Nietzsche became increasingly disillusioned with Wagner, and his mature works, starting with Human, All-Too-Human, show Nietzsche finding his own distinctive voice, free from Wagner’s influence. In particular, Nietzsche became disgusted with Wagner’s shallow pro-German nationalism and his anti-Semitism. In contrast to Nietzsche’s later biting attacks on nationalism, The Birth of Tragedy bears Wagner’s influence in its pride in German culture and its hope that a purified German culture can rescue European civilization from the deadening influence of Socratic rationalism.