One Microbe, One Vote?

Carl Abbott dives into Joan Slonczewski’s “Minds in Transit.”

By Carl AbbottAugust 14, 2025

• SF

• Science & Technology

SCIENCE FICTION LUMINARY Joan Slonczewski, who is also professor of biology at Kenyon College, enjoys pushing the limits of biological speculation while questioning social hierarchies and societal assumptions. Their new novel, Minds in Transit, accomplishes both. Central to their speculation is a simple but startling question: can a microbe be a person?

Minds in Transit takes place on paired worlds, Valedon and Shora, that Slonczewski first introduced in A Door into Ocean (1986) and has continued to explore in subsequent novels in their Elysium Cycle series. Although it stands alone, Minds in Transit, the fifth in the sequence, is a direct sequel to Brain Plague (2000), with the same setting and an overlapping cast of human and nonhuman characters.

Two thousand years after the events of A Door into Ocean, Iridis is still the capital of Valedon, and the city has grown vastly larger but still with recognizable landmarks—think the Rome of Cicero expanded to the Rome of Federico Fellini. Traditional biological humans share the city with hybrid human-gorilla “sims,” genetically modified Sharers from Shora, and sentient artificial intelligences that assume forms ranging from paparazzi drones to a living house. Floating cities that dot the Shoran sea are home to Elves, humans who have genetically engineered themselves to live very long lives.

The novel’s central figure is Chrysoberyl, a visual artist who shapes three-dimensional patterns of light, as well as a dynatect, someone who designs living buildings, districts, and complete cities. Chrys is the host and controlling “god” for a population of intelligent ring-shaped microorganisms who live in her cerebrospinal fluid and build cities in the weblike membranes that cushion her brain against her skull. The novel’s point of view alternates between that of Chrys, over several eventful months of her life, and that of the fast-living microbes, over many generations.

Chrys’s “godhood” distinguishes her as part of a small group of humans who are trying to establish a way to coexist with the microorganisms. On their planet of origin, the microbes are the dominant species, but they are new arrivals to Valedon and Shora and ill-adapted to humans. As such, they are regarded as a frightening brain plague; they can take control of their host by overloading the latter’s pleasure centers with dopamine and turning them into arsenic addicts (arsenic is an element essential for their particular microbial biology). The “micros” communicate among themselves by sensing and transmitting chemicals, and with humans by flashing words onto the host’s retina. Chrys and her colleagues try to domesticate and control their own populations by providing or withholding pleasure chemicals to enforce their commands as benevolent but still all-powerful deities. An hour of human time passes as a microbe year; if Chrys oversleeps, her microbes wonder if their god has forsaken them.

Slonczewski imagines the microbes as unique individuals with different talents and personalities, from chess fanatics to artists to politicos. The community within each host develops a distinct culture; the equivalent of a society of accountants may dominate one host, for example, while artists and mathematicians dominate another. Humans pass microbe representatives back and forth by using patches that send visitors into their bloodstreams—a literal example of “minds in transit” from one host to another. Micros debate capitalism and free trade, but they agree that immigration of micros from other hosts brings the benefits of new ideas and new genetic material. The micro civilizations can also look after their own interests. Finding themselves too dependent on arsenic, for example, they deliberately develop the ability to use antimony instead, and then the whole array of lanthanide elements (the book is a refresher on the periodic table).

Because they live so fast, micros can often outthink their slower human hosts. Their communities can function as living nanoscale parallel processors. Chrys comes to depend on their ideas to enhance her art and on their computational capacity to devise solutions to her architectural and city planning problems. The city of Iridis is woven from a semi-intelligent plasmatic material that can flex and expand on its own, repair faults, and be shaped and reshaped as needs change. Buildings send taproots deep into bedrock for the minerals needed to maintain themselves and grow. Chrys and her microbes have an ongoing job of repairing the Comb, a building developed by a noted artist whose ego got in the way of sensible design. Even while Chrys is at work, the building is growing, adding new floors beneath the old and reconfiguring offices and laboratories week to week. With this commission on her résumé, she is designing an entire new city on Shora for sentient AIs only. It turns out that trying to please a committee of supersmart AIs is just as big a pain as working with a committee of humans.

Slonczewski uses Chrys’s commissions to poke fun at ego-driven design, but Iridis has deeper problems. The massive city spans 50 miles and reaches 100 levels layered by class and function—elites on the top levels, middling classes and commercial sectors below, and the vibrant and dangerous Underworld full of immigrants and undocumented sentients just above bedrock (I envision something like the Los Angeles streets of the 1982 film Blade Runner). Towering supercities where height equates with social status are not new in science fiction (see Robert Silverberg’s 1971 novel The World Inside), but Iridis is not solid steel and concrete. Rather, it’s a living body that can grow, but which can also wither and even die.

Chrys’s microbes devise an urban renewal plan to upgrade the existing Underworld communities, which have the sorts of self-organization and cohesion that social scientists find in marginal neighborhoods in places as different as Southern California and Rio de Janeiro. The Iridian elites prefer to relocate the residents, clear the lowest levels, and fill those floors in. They have a real worry: cancers are eating the cellular material that supports the city, undermining its foundation and threatening its collapse.

Slonczewski thus makes the metaphorical urban blight of 20th-century city planning into a literal disease. In so doing, they bring the idea back to its origins in the work of early 20th-century plant ecologists that sociologists adapted to urban change in the 1920s and 1930s. Historian Jennifer S. Light, in The Nature of Cities: Ecological Visions and the American Urban Professions, 1920–1960 (2009), explains that those urban ecologists in fact saw what they called “urban blight” not as a metaphor but as a cancerous reality of urban landscapes. Minds in Transit makes this metaphor into a driver of the plot when the cancerous growths trigger a devastating city-quake that upends the ruling elite and paves the way for a humane reconstruction of the Underworld community.

Writing microbes as recognizable and sympathetic individuals allows Slonczewski to center the question of personhood. The microbes are intelligent, argumentative, and ambitious. They have politics, elections, and coups. They also live in peril; humans don’t hesitate to destroy entire populations that have gone rogue. These overlords subject the obedient communities to constant monitoring and cull them if they begin to stray. Chrys’s microbes tremble at the member of her circle whom they call the Death Lord, who bluntly says, “[I]f they cause trouble, they’re done.” Does the Death Lord eliminate parasites or commit genocide?

The question of personhood is already problematic in the novel’s setting: traditional humans harbor prejudice against sims, and Valedon grants personal rights to AI sentients of a certain size but votes down a proposal to eliminate the limit—to the distress of Chrys’s intelligent house. Things become even more complicated when the communication satellites that serve the two worlds become self-aware and begin to produce art in the form of vast auroras that disrupt transmissions.

So what is the status of the intelligent microbes? Are they extremely bright domestic animals or are they people? Are they sentient slaves who lack civil rights, similar in some ways to Black Americans after the Supreme Court’s 1857 Dred Scott decision? Or, because they necessarily interact with the macrolevel world through their hosts, are they colonial subjects whose imperial masters control commerce with the rest of the world? Chrys the god enjoys having a worshipful congregation of millions, while Chrys the artist sees herself as the benevolent patron to useful dependents.

Slonczewski’s goal is to ask readers to reflect on what makes someone a person. The traditional human baseline has already been challenged with sims, Elves, Sharers, and sentient AIs, so why not microbes? If the criterion is to have active and lively minds, the microbes have the culturally stagnant Elves beat. If it is the ability to work in groups toward common ends, the microbes again qualify.

The importance of social connection has been central to Slonczewski’s work, from the Quaker-tinged communities of Sharers in A Door into Ocean to the vital society that Chrys’s microbes create for themselves. Science fiction readers might contrast Minds in Transit with Greg Bear’s Blood Music (1985), in which modified cells introduced into a human body evolve intelligence and eventually transcend physical limitations. Slonczewski is much more practical; microbial societies remain firmly based inside human bodies while helping to shape the macroscale world of human cities. This social embeddedness makes a powerful argument for their personhood.

Always sympathetic to her microbes, Chrys is still shocked to hear a friend rail against their treatment: “Atrocity, starvation, mass extermination. […] Inhumanity on a scale beyond our comprehension.” The friend’s passion forces Chrys to finally confront her own hypocrisy in thinking of her microbes as individuals while still treating them as tools. She realizes that she and her colleagues are complicit in the slaughter of innocents. In the wake of the city-quake, the ruling oligarch appoints Chrys to a government ministry where she has the authority to declare the right of personhood to be universal for all feeling beings. “Universal rights begin at home, in the smallest places—the place of our own bodies,” one minister declares. “That is where every micro person seeks equal justice, equal opportunity, and equal dignity without discrimination.” The Universal Declaration of Human Rights has become a Universal Declaration of Sentient Rights. Over the course of the novel, microbial minds have been in transit from beings without legal status to citizens with civil rights. Left undecided is whether humans are willing to accept the notion of one microbe, one vote.

It is not hard, at least for some, to think about claims to personhood for animals like crows and corgis, especially since they display clear intellectual capacities, as political philosopher Martha C. Nussbaum has recently argued. Readers of science fiction often readily accept David Brin’s choice of human-scale dolphins and chimpanzees as potential peers. Slonczewski, in contrast, thinks this is too easy; they push us to consider our relationships with living entities that we can’t directly anthropomorphize as cute, playful, or majestic. For the purpose of storytelling, Slonczewski depicts Chrys’s passengers as sometimes playful and sometimes arrogant, but they also want us to consider the potential personhood of not only these imagined creatures but also the real-life microorganisms that share our skin and gut, and perhaps other living communities like forests and rivers. Doing so requires thinking about collectivities and ecosystems in addition to individuals, and this mode of thought emphasizes Slonczewski’s focus on the importance of connected communities.