Siegfried (with his muse Brünnhilde) as the artist-hero to whom Wagner (and Wotan) turned instead for an inward, subjective redemption, rescues Siegfried from the demotion to which Scruton, Kitcher, and Schacht would reduce him.
A cryptic basis for the plots of the first three of the four parts of the Ring can be found in a couple of pages from Wagner’s autobiography Mein Leben [P. 430-431] in which he discusses the influence of several of Feuerbach’s books on him. An initial spark for Wagner’s allegory in The Rhinegold about the origin of the gods in our human psychology, our capacity for self-deception, can be seen in his remark that in his The Essence of Christianity Feuerbach undertook “… the interpretation of religion from a purely psychological standpoint.” The plots of The Valkyrie, in which the moral hero and social revolutionary Siegmund offers one form of post-religious redemption by taking action in the political and social world to right its wrongs, and Siegfried, in which the secular artist-hero Siegfried and his muse of unconscious artistic inspiration Brünnhilde fall heir to the legacy of dying religious faith represented by Wotan, are outlined in essence, respectively, in Wagner’s statement that “I found it elevating and consoling to be assured [by Feuerbach] that the sole authentic immortality adheres only to sublime deeds and inspired works of art.” Of the two kinds of post-religious immortality, or sacredness, which replace religious faith’s debunked bid for transcendence Wagner alludes to here, Siegmund’s, Sieglinde’s, and Brünnhilde’s heroic actions in The Valkyrie are “sublime deeds,” and Siegfried’s inspiration by his muse Brünnhilde in Siegfried is supposed to produce “inspired works of art.” Wagner was even more explicit in his explanation that the heritage of dying religious faith (Wotan) is carried on by inspired secular art, and his own ‘artwork of the future’ in particular, once we recognize that what in religious times we’d called the immortal gods was merely a product of our natural aesthetic impulse, in his observation that “The fact that he [Feuerbach] proclaimed what we call ‘spirit’ to lie in our aesthetic perceptions of the tangible world, together with his verdict as to the futility of philosophy, was what afforded me such useful support in my conception of a work of art which would be all-embracing while remaining comprehensible to the simplest, purely-human power of discernment, … in ‘the artwork of the future’ … .” Wagner alludes here specifically to the “Wonder” of his musical motifs of foreboding and reminiscence, through which a complex drama can attain a unity of time, space, and naivety otherwise unavailable to conventional drama.
But what can’t be found explicitly laid out in Feuerbach’s writings, and can only be guessed at (as Wagner evidently did) through imaginative speculation on the most far-reaching conclusions which follow from Feuerbach’s materialist premises and some contradictions imbedded in them, is that eventually inspired secular art itself, in which dying religious faith (Wotan’s thought) had retreated to the safety of feeling (Wotan’s music, Brünnhilde, man’s aesthetic sense), might someday have its unspoken secret, its covert championing of religious man’s futile longing for transcendent value and meaning in the face of science, exposed to the light of day and destroyed, just as religious faith had been beforehand. Siegfried, in other words, succumbs, as Brünnhilde said, to the same Ring Curse (of consciousness) that doomed Wotan and the gods. This is the whole substance of the last part of Wagner’s Ring, Twilight of the Gods. It is, I think, extremely significant that Twilight of the Gods in its original iteration as Siegfried's Death was the first of the four Ring dramas which Wagner wrote, in view of the astonishing fact that it's precisely here, in the Ring's climax, that Wagner drew his most original conclusions from hints in a few passages from Feuerbach's writings, conclusions Feuerbach never drew (at least in his four books which influenced Wagner in creating his Ring).