I’m a huge fan of Gadamer, and in this context this means that there is a mostly coherent Nietzsche-as-I-appropriate-him, or Nietzsche-for-me, which we might call an “aspect” of Nietzsche.
With that disclaimer, I tend to think of him as a response to Schopenhauer. More exactly he is responding to a “vision of horror” that Schopenhauer disclosed for him. Consider this passage from an early work:
For we must know that in the rapture of the Dionysian state, with its annihilation of the ordinary bounds and limits of existence, there is a lethargic element, wherein all personal experiences of the past are submerged. It is by this gulf of oblivion that the everyday world and the world of Dionysian reality are separated from each other. But as soon as this everyday reality rises again in consciousness, it is felt as such, and nauseates us; an ascetic will-paralysing mood is the fruit of these states. In this sense the Dionysian man may be said to resemble Hamlet: both have for once seen into the true nature of things, —they have perceived, but they are loath to act; for their action cannot change the eternal nature of things; they regard it as shameful or ridiculous that one should require of them to set aright the time which is out of joint. Knowledge kills action, action requires the veil of illusion—it is this lesson which Hamlet teaches, and not the cheap wisdom of John-a-Dreams who from too much reflection, as it were from a surplus of possibilities, does not arrive at action at all. Not reflection, no!—true knowledge, insight into appalling truth, preponderates over all motives inciting to action, in Hamlet as well as in the Dionysian man. No comfort avails any longer; his longing goes beyond a world after death, beyond the gods themselves; existence with its glittering reflection in the gods, or in an immortal other world is abjured. In the consciousness of the truth he has perceived, man now sees everywhere only the awfulness or the absurdity of existence, he now understands the symbolism in the fate of Ophelia, he now discerns the wisdom of the sylvan god Silenus: and loathing seizes him.
In my view, he identifies with Hamlet, or with an aspect of Hamlet. Freud’s Hamlet is someone else, and so is Bloom’s. This sounds to me like some rapturous expansion of self followed by a nauseating return to the little practical ego and its now-petty self-preserving worries.
What is this “appalling truth” ? Unjust/absurd suffering that cannot be extinguished. A vivid sense that his own action is powerless to divert “the eternal nature of things.” Would killing Claudius achieve anything “substantial” ?
What is substantial ? Something that lasts forever ? But there’s a “factory” that will churn out a thousand more Claudius types, namely that insane/demonic will-to-live-by-consuming-to-replicate.
Is this a resentment of “finitude” in the sense of confinement to what is merely a passing show ? “For these are actions that a man might play / But I have that within that passes show.”
He’s also obsessed with masks and surfaces that conceal depths in later work.
In the writings of a recluse one always hears something of the echo of the wilderness, something of the murmuring tones and timid vigilance of solitude; in his strongest words, even in his cry itself, there sounds a new and more dangerous kind of silence, of concealment. He who has sat day and night, from year’s end to year’s end, alone with his soul in familiar discord and discourse, he who has become a cave-bear, or a treasure-seeker, or a treasure-guardian and dragon in his cave—it may be a labyrinth, but can also be a gold-mine—his ideas themselves eventually acquire a twilight-colour of their own, and an odour, as much of the depth as of the mould, something uncommunicative and repulsive, which blows chilly upon every passer-by. The recluse does not believe that a philosopher—supposing that a philosopher has always in the first place been a recluse—ever expressed his actual and ultimate opinions in books: are not books written precisely to hide what is in us?—indeed, he will doubt whether a philosopher CAN have “ultimate and actual” opinions at all; whether behind every cave in him there is not, and must necessarily be, a still deeper cave: an ampler, stranger, richer world beyond the surface, an abyss behind every bottom, beneath every “foundation.” Every philosophy is a foreground philosophy…Every deep thinker is more afraid of being understood than of being misunderstood.