Brain Plague [Hardcover]

These are the complex and puzzling issues raised in Joan Slonczewski's latest novel Brain Plague. In the far future, humanity has spread throughout the galaxy. In addition to normal humans, there are "elves" (genetically engineered near-immortals), simians (human/ape hybrids), sentients (artificial intelligences), and a variety of other creatures (including organic, self-aware buildings who negotiate rental agreements with their tenants).

Despite the advances of technology, all is not well in the universe. Humans still suffer addictions and homelessness. Violence still occurs all too often. And in the background, a terrible plague has been raging through space - a "brain plague" in which intelligent "micros" invade human hosts and turn them into slaves. But just like human beings, there are good micros and bad ones. The good ones are part of a carefully monitored program in which human hosts are matched with colonies of microbes. The resulting symbiotic relationship provides the microbes with an ideal living environment (and a "god" to worship); it provides the host with the equivalent of a million microscopic parallel processors to apply to any task he or she might imagine.

Chrys, a young and talented (but starving) artist volunteers for the "brain enhancer" program, accepting a colony of microbes. They communicate with her via nanotechnology implanted in her optic nerves. Thus begins Chrys's journey, learning to live with her new partners, suffering through the prejudice and hatred of others, reaching self-actualization in her art, and risking her life to discover the truth about the Brain Plague.

Joan Slonczewski (author of six previous novels) has drawn upon her background as a molecular biologist to bring us something very different from the usual science fiction tale. While many SF novels find ways to bend the rules of physics, Brain Plague finds ways to bend the rules of the mind, and tinkers with our concept of individuality.

If any complaint can made against this novel, it's that so much is thrown at the reader in the first chapter it can be overwhelming. This is partly due to the fact that this novel, while not technically a sequel, is based in the same universe as her previous novels (thus some prior knowledge of these would doubtless be helpful); and partly due to Dr. Slonczewski's extremely active imagination. Nonetheless, the tale is well-told, drawing the reader in despite its complexity. All in all, it's an engrossing novel.

These microbes, you see, are not just intelligent. They are also social, in the way that humans are social (not bees). Individuals retain enough individuality to have clashing wishes and clashing ideologies. So microbial societies develop distinct cultures -- as variegated as human societies. Add to this that they live and die radically faster than humans. For good measure, on their home planet they evolved to colonize non-sentient animals of approximately human scale. So on invading human hosts, their initial impulse is to control these hosts as they would control mindless beasts. In "The Children Star", humans almost decided to wipe them out, but relented because the colonies in some humans developed more symbiotic cultures, with dazzling services to offer.

Now they've been around a while, and human society is caught in a maelstrom. Virulent microbial societies have become a "brain plague", controlling their environments -- their hosts -- in short-sighted, destructive ways. A secret community of carriers, however, has learned to pass around microbes with friendlier or more submissive cultures. Living as fast as they do, the microbes also think faster, and confer great benefits as brain enhancers. Besides which, they're company to the lonely human soul, and some worship their hosts as "gods". It's a dangerous game, however. Generations of microbes parade by in what for humans is a short while. New generations bring new fashions and ideas. A human carrier can wake in the morning to find that overnight there has been a revolution. Now the microbes are bad.

That's all I'll say about plot, though there's plenty more. What about plausibility? The one and only attempt to make "micropeople" plausible occurs early on, when the protagonist of the story objects, "It's absurd. Nothing that small can have enough ... connections to be self-aware." The doctor answers, "Self-awareness occurs in sentients with about a trillion logic gates. A micro cell contains about ten times that number of molecular gates." Gating what, though, and how? Electrical signals? Connections in humans take place at synapses, where electrical signals are transmitted by chemical packets that take about 15 milliseconds to cross the gap. What sorts of pathways are available inside a microbe, and what timings are possible at the connections? Where signals have to be summed, what would be the thresholds and rise times? These timings could set a limit to the speed of thinking. The story has to attribute fast thinking to the micropeople, because microbial lives would otherwise be too short to learn much.

Assuming no questions of this sort pose a "showstopper", I think that the micropeople of "The Children Star" and "Brain Plague" raise a new science fiction topic as fundamental as space travel. After all, there could be "macropeople" as well. James Lovelock, when he first put forth the "Gaia" hypothesis, was careful to disavow any implication that "Gaia" was conscious; his speculation was only about an autonomic control system. (Later he wavered and personalized it a little.) Similarly, Richard Dawkins has been careful to declare that "The Selfish Gene" is only a metaphor. But why shouldn't there be sentient entities at more than one scale, operating at more than one pace? How would we ever discover if there were? How to communicate? And what would be the consequences for the discussion of evolution, if microbial entities were found to be conscious players? This could be big.