What common features do the diverse books we have considered share? To those characteristics we pointed out in attempting to define science fiction in the introduction we can now add a few more.
In all these works personal identity is continually in flux. Attanasio's Sumner Kagan shifts from self to self throughout Radix. Burton in Farmer's Riverworld has to assume a reality he is not certain he possesses. Aldiss's Gren shifts in character, and his environment to match during his contact with the morel. The protagonist of Silverberg's Nightwings changes himself as often as he changes his guild. Mutation is a constant theme in this book, as in Hothouse, where we are continually made aware of how the plants have evolved to stranger forms to survive; and in Asimov's Foundation trilogy a shape-shifting mutant leads the Foundation to power and near disaster in the galaxy. In Wolfe's Book of the New Sun identity is so thin-walled that one character can participate in another, and one phenomenon or event is part of or interchangeable with others before or after it. The three human brains of the Ship in Simak's Shakespeare's Planet have to learn through the book to merge their remaining individualities into a corporate self. In Pohl's stories reality is continually being altered — the creatures in the museum brought to ghostly life and the magician himself turned to a ghost, the changing of the post-holocaust worlds of 'Target One' and 'Let the Ants Try', the perversions of fact by Rafferty, the transformation of society by Cheery-Gum.
At the same time identity is constantly in doubt. Asimov's Second Foundationers cannot be traced; and every assumption made about Seldon's Plan has to be altered. Yattmur in Hothouse does not know whether she is speaking to Gren or the morel. Paul Atreides and those about him in Dune have to discover whether he is the Kwisatz Haderach. The world of Nightwings is anonymous and nameless until the truth about humanity can be found. Throughout To Your Scattered Bodies Go it is not known whether