This is one of the most disturbing posthuman science fiction stories I've ever read (that's a good thing). In Nothing Human, aliens known as the "pribir" arrive in 2005, just as humanity is beginning to tinker with genetic engineering in earnest. Having prepared for their arrival by tweaking the genes of several in vitro babies, all of whom are now thirteen years old, the pribir communicate by sending olfactory information (smells) that these "pribir children" can receive as images. After a rocky start (the pribir destroy an orbiting nuclear power plant because it "isn't the right way" and "harms our genes"), the pribir share a cure to cancer and malaria. But it all starts to go wrong when some of the pribir children elect to go aboard the pribir spaceship....
Although nominally set Twenty Minutes into the Future, I describe Nothing Human as posthuman fiction because it deals with the motifs of humanity, genetics, and evolution. At its core, the novel asks the question "what does it mean 'to be human'?" by looking at the effects of genetic modification on a microcosm of the human species. Nancy Kress also touches on the concept of directing the evolution of one's own species.
These issues are becoming increasingly relevant to contemporary society. We've sequenced the human genome and are taking the steps toward developing viable gene therapy. It's only a matter of time before we have the capability to radically alter ourselves on the genetic level. Nicolas Wade briefly mentions this in the last chapter of Before the Dawn, his genetic history of humanity. One of the possible futures for humanity he postulates is a trend toward greater diversity within the species. Kress takes the idea and runs with it, for the pribir aren't as "alien" as we first think. In fact, they claim to be descended from humans, taken from Earth by real aliens, whose evolution was then accelerated. We only meet two pribir individuals; they look human but claim this was an intentional decision to appear less threatening to the humans of Earth. This and several other events imply that physical forms among the pribir vary immensely.
The idea of one's physical form--that is, the expression of one's genome--dictating whether or not one is human recurs throughout Nothing Human. Although the pribir appear human, they clearly have abilities beyond the ordinary humans of Earth. The pribir children, and their children, display similar (but not as great) abilities, such as an enhanced immune system. For all their tinkering, the pribir claim they're trying to help humanity survive the human-made ecological disaster on Earth, through genetic adaptation and directed evolution. Yet when they propose drastic measures that result in the birth of children who look and communicate in drastically non-human ways, the reader has to wonder: is this saving the human race or subsuming it?
Obsessed as they are with saving humanity, the pribir seldom pause to consider what is human. "Mostly human genes" is a good enough explanation for them. Other characters consider whether humanity is conferred through memory, thought and personality, culture, other traits that are not purely biological. In either case, the definitions always seem inadequate. This reminds us that the boundaries among species are not as stark as anthropologists and zoologists always make them appear. We only consider ourselves distinct from our evolutionary predecessors because they're long gone and we remain (so far). If "more primitive" human beings still lived somewhere, would we consider them human? Where do we draw the line?
I know I keep going on about the pribir, but honestly, I found them quite fascinating in their role as alien benefactors. We only meet two: Pete and Pam. And unlike the ethereal, serene, wise aliens we always see on television and movies, Pete and Pam are quite immature, even childish by our standards. They repeatedly lament humanity's stupidity and the unanticipated ability of Earth's nations to destroy each other and squander their natural resources. Pam in particular seems bewildered by the animosity toward the pribir's attempt to help put humanity on the path to "the right way." I loved this portrayal of the alien benefactors as petty and unsympathetic, dangerous more because they're so ineffectual than because of any malevolence on their part.
Additionally, Pete and Pam seem to have trouble understanding or anticipating the behaviour of the humans they're trying to help, demonstrating a remarkable detachment from "contemporary" human society's mores. Before I judge them based on this fact, however, I have to stop and wonder what it would be like if our positions were reversed. Suppose I ended up among an ancient civilization, with little information on that civilization's attitudes toward issues like abortion, childbirth, science, etc.? Suppose I'd only been monitoring that civilization through its cultural outlets for a couple of decades (like Pete and Pam do with television broadcasts), and as a result, my information is slightly dated or skewed. It's fair to say I'd probably find many of their customs barbaric by my standards. Still, the amount of alienness of Pete and Pam is disconcerting at times, for several reasons. The most important reason, however, is the most chilling: in a few centuries, assuming humanity survives as a species, we could be them.
Alongside the not-quite-alien pribir, the regular and modified human characters seem like they are portrayed in Technicolour. All of their actions take on a new level of meaning along a continuum: there are those who end up supporting the efforts of the pribir (ultimately Lillie) and those who reject the pribir and their proposed solution (most notably, some of Lillie's children). Kress plays up the moral ambiguity, and to good effect: I couldn't really side with one camp or the other on this issue. Ideally I found myself wishing for a magic bullet that would let the species stay the same even as dangerous toxins built up in Earth's animal and plant life; of course, Kress had no interest in taking the easy way out.
Indeed, Nothing Human asks only tough questions, questions that have no easy answer. It is a superb thought experiment involving genetics, ecology, and alien encounters. I found it difficult to become attached to any of the characters, yet that didn't stop me from enjoying the book's plot or its themes. I definitely recommend this to anyone open to science fiction.