Re Wolfe's remarks in that SFBC catalogue: beware
Genes bearing gifts. The idea that Horn/Silk's astral
self is the ghost of Malrubius is very creaky, in
flagrant contradiction of everything imparted
concerning this aquastor or eidolon in THE BOOK OF THE
NEW SUN. Wolfe's SFBC Note actually means in all
likelihood that by accepting the existence of the
paranormal--astral projection and the like--we also
accept the literal reality of ghosts of the dead. Just
as the ghost of Pike was indeed Pike's spirit, so the
ghost of Malrubius is indeed the deceased Master
Malrubius. Nothing more complicated than that...
--Nick Gevers.