The book chronicles the fictitious travels and speeches of Zarathustra. Zarathustra's namesake was the founder of Zoroastrianism, usually known in English as Zoroaster (Avestan: Zaraϑuštra). Nietzsche is clearly portraying a "new" or "different" Zarathustra, one who turns traditional morality on its head. He goes on to characterize "what the name of Zarathustra means in my mouth, the mouth of the first immoralist:"
For what constitutes the tremendous historical uniqueness of that Persian is just the opposite of this. Zarathustra was the first to consider the fight of good and evil the very wheel in the machinery of things: the transposition of morality into the metaphysical realm, as a force, cause, and end in itself, is his work. [...] Zarathustra created this most calamitous error, morality; consequently, he must also be the first to recognize it. [...] His doctrine, and his alone, posits truthfulness as the highest virtue; this means the opposite of the cowardice of the "idealist” who flees from reality [...]—Am I understood?—The self-overcoming of morality, out of truthfulness; the self-overcoming of the moralist, into his opposite—into me—that is what the name of Zarathustra means in my mouth.
— Nietzsche, Ecce Homo, "Why I Am a Destiny", §3, trans. Walter Kaufmann
Zarathustra has a simple characterisation and plot, narrated sporadically throughout the text. It possesses a unique experimental style, one that is, for instance, evident in newly invented "dithyrambs" narrated or sung by Zarathustra. Likewise, the separate Dithyrambs of Dionysus was written in autumn 1888, and printed with the full volume in 1892, as the corollaries of Zarathustra's "abundance".
Some speculate that Nietzsche intended to write about final acts of creation and destruction brought about by Zarathustra. However, the book lacks a finale to match that description; its actual ending focuses more on Zarathustra recognizing that his legacy is beginning to perpetuate, and consequently choosing to leave the higher men to their own devices in carrying his legacy forth.
Zarathustra also contains the famous dictum "God is dead", which had appeared earlier in The Gay Science. In his autobiographical work Ecce Homo, Nietzsche states that the book's underlying concept is discussed within "the penultimate section of the fourth book" of 'The Gay Science' (Ecce Homo, Kaufmann). It is the eternal recurrence of the same events.
This concept first occurred to Nietzsche while he was walking in Switzerland through the woods along the lake of Silvaplana (close to Surlej); he was inspired by the sight of a gigantic, towering, pyramidal rock. Before Zarathustra, Nietzsche had mentioned the concept in the fourth book of The Gay Science (e.g., sect. 341); this was the first public proclamation of the notion by him. Apart from its salient presence in Zarathustra, it is also echoed throughout Nietzsche's work. At any rate, it is by Zarathustra's transfiguration that he embraces eternity, that he at last ascertains "the supreme will to power". This inspiration finds its expression with Zarathustra's roundelay, featured twice in the book, once near the story's close:
|“||O man, take care! What does the deep midnight declare? "I was asleep— From a deep dream I woke and swear:— The world is deep, Deeper than day had been aware. Deep is its woe— Joy—deeper yet than agony: Woe implores: Go! But all joy wants eternity— Wants deep, wants deep eternity."||”|
Another singular feature of Zarathustra, first presented in the prologue, is the designation of human beings as a transition between apes and the "Übermensch" (in English, either the "overman" or "superman"; or, superhuman or overhuman. English translators Thomas Common and R. J. Hollingdale use superman, while Kaufmann uses overman, and Parkes uses overhuman. Martin has opted to leave the nearly universally understood term as Übermensch in his new translation). The Übermensch is one of the many interconnecting, interdependent themes of the story, and is represented through several different metaphors. Examples include: the lightning that is portended by the silence and raindrops of a travelling storm cloud; or the sun's rise and culmination at its midday zenith; or a man traversing a rope stationed above an abyss, moving away from his uncultivated animality and towards the Übermensch.
The symbol of the Übermensch also alludes to Nietzsche's notions of "self-mastery", "self-cultivation", "self-direction", and "self-overcoming". Expounding these concepts, Zarathustra declares:
"I teach you the overman. Man is something that shall be overcome. What have you done to overcome him?" "All beings so far have created something beyond themselves; and do you want to be the ebb of this great flood and even go back to the beasts rather than overcome man? What is the ape to man? A laughingstock or a painful embarrassment. And man shall be just that for the overman: a laughingstock or a painful embarrassment. You have made your way from worm to man, and much in you is still worm. Once you were apes, and even now, too, man is more ape than any ape." "Whoever is the wisest among you is also a mere conflict and cross between plant and ghost. But do I bid you become ghosts or plants?" "Behold, I teach you the overman! The overman is the meaning of the earth. Let your will say: the overman shall be the meaning of the earth! I beseech you, my brothers, remain faithful to the earth, and do not believe those who speak to you of otherworldly hopes! Poison-mixers are they, whether they know it or not. Despisers of life are they, decaying and poisoned themselves, of whom the earth is weary: so let them go!"
— Thus Spoke Zarathustra, Prologue, §3, trans. Walter Kaufmann
The book embodies a number of innovative poetical and rhetorical methods of expression. It serves as a parallel and supplement to the various philosophical ideas present in Nietzsche's body of work. He has, however, said that "among my writings my Zarathustra stands to my mind by itself" (Ecce Homo, Preface, sec. 4, Kaufmann). Emphasizing its centrality and its status as his magnum opus, Nietzsche stated that:
With [Thus Spoke Zarathustra] I have given mankind the greatest present that has ever been made to it so far. This book, with a voice bridging centuries, is not only the highest book there is, the book that is truly characterized by the air of the heights—the whole fact of man lies beneath it at a tremendous distance—it is also the deepest, born out of the innermost wealth of truth, an inexhaustible well to which no pail descends without coming up again filled with gold and goodness.
— Ecce Homo, Preface, §4, trans. Walter Kaufmann
Since many of the book's ideas are also present in his other works, Zarathustra is seen to have served as a precursor to his later philosophical thought. With the book, Nietzsche embraced a distinct aesthetic assiduity. He later reformulated many of his ideas, in Beyond Good and Evil and various other writings that he composed thereafter. He continued to emphasize his philosophical concerns; generally, his intention was to show an alternative to repressive moral codes and to avert "nihilism" in all of its varied forms.
Other aspects of Thus Spoke Zarathustra relate to Nietzsche's proposed "Transvaluation of All Values". This incomplete project began with The Antichrist.