Lyric discussion by envelope 

It's about the seeming futility of belief in a higher being or afterlife-based paradigm.
The first phrase is the man experiencing his own death and seeing nothing but himself dying; there is no afterlife. When I listened to a long, long time ago I imagined that the second phrase was, as the reference to the autobiographical book above says, that this man is climbing, making an Ascent to find separation (as is assumedly was found in Bowie's own practice of meditation and yoga and referenced in other songs on this album). The album cover has Bowie standing with his back to the viewer in an A-frame pose with the Union Jack lines in his coat further emphasizing this letter...I hope you follow the symbolism so far as to how it relates to the lyrics. "Turn to question the mountain / Why pigs can fly / It's nothing at all," seems to be saying that even in this non-theist paradigm there is no escape or comfort or redemption gained from attaining what is implied by going "beyond the yoga zone" and the "frail form" ("is drifting" like snow, "old snow", like ashes). The phrase "why pigs can fly, it's nothing at all," seems to be a recognition that this "enlightenment" offers nothing...he climbed the mountain to reach "heights" that "pigs" have reached without the same effort/mindfulness/practice.
And of course, "I praise to you, nothing ever falls away" is the man's reaction to the failure of prayer and belief. When I say "man" in the above writing I speak of the character in the lyrics and not Bowie but some years prior he had written "Loving the Alien" which both in lyrics and imagery (in the video) deal with similar issues of prayer and meditation based paradigms.

@envelope The futility idea is incorrect I believe as David Bowie kept looking for spirituality on a journey of sorts until his death. I believe that this is rather about Bowies previous abandoned Bhuddism and "it's nothing at all" is rather about Bowie not finding any satisfaction in Bhuddism.

Also fucking hell I am seven years late.

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