The demo featured Sebastian Knight and Joakim Ekroos, who would not be retained as permanent members after production.
In The Real Life of Sebastian Knight, Nabokov says that the soul "is but a manner of being," not a constant entity.
That last one reminds me of a passage in a favorite book of mine, Nabokov's The Real Life of Sebastian Knight:
The narrator, V., is absorbed in the composition of his first literary work, a biography of his half-brother the famous Russian-born English novelist, Sebastian Knight (1899-1936).
Sebastian Knight had died the night before.
The novel concludes with a philosophical reconciliation of Sebastian's life, and a final implication that V. himself is Sebastian Knight, or at least an incarnation of his soul.
Nabokov's friend, correspondent, and sometime antagonist Edmund Wilson called Sebastian Knight his favorite among the author's works.
Rimmon, Shlomith: "Problems of Voice in Nabokov's The Real Life of Sebastian Knight".
Nabokov, Vladimir The Real Life of Sebastian Knight.
Vladimir Nabokov refers to Mrs Grundy in his novel The Real Life of Sebastian Knight (1941).