Children of Memory, by Adrian Tchaikovsky

Adrian Tchaikovsky’s Children of Memory (2022; but published in the US on January 31, 2023) is the third science fiction novel in a series that started with Children of Time (2015), and continued with Children of Ruin (2019). The books are concerned with different varieties of sentience and intelligence. The background scenario for this far-future series is that human beings on Earth set forth with an ambitious project to terraform planets across the galaxy, but that the project and never completed. The terraforming project involves creating a livable climate, and stocking the planet with a diverse enough range of Earth organisms to create a functioning ecology. After this, either the planet can be inhabited by human beings, or else the world is seeded with a plasmid that provokes genetic mutations to raise another species to human-level intelligence. But due to troubles on Earth, the plan is never quite realized. In Children of Memory, instead of uplifting nonhuman primates, the plasmid creates a species of intelligent Portia spiders. The novel traces the stages of the spiders’ rise to civilization, and considers how their mentality might be different from a human one due to the intrinsic biological differences between the species. In Children of Ruin, octopuses on a water world are boosted to human-level intelligence; again, the novel explores how such a cephalopod intelligence would be different from either a primate or an arachnid one. In addition, in the second novel, the human beings, spiders, and octopuses also encounter an alien lifeform that is something like a parasitic slime mold. The slime mold assimilates, stores, and remembers the mentality and the experiences of any other living species that it encounters. This is at first a danger to the other sentient species: the slime mold transforms all the mindful entities that it encounters into more versions of itself. But eventually, this behavior is changed from a predatory, parasitic lifestyle into one of symbiotic mutualism. The slime mold craves novelty and new experiences; eventually it realizes (or is persuaded) that it can get more of these if it does not assimilate other organisms, but rather coexists alongside them and shares their experiences.

[WARNING: WHAT FOLLOWS CONTAINS SPOILERS] Children of Memory introduces an additional uplifted species: Corvids (the exact species is not specified; they seem to be a crow and raven hybrid). The Corvids do not get the plasmid that the spiders and octopuses got in the previous volumes; rather, they evolve greater intelligence on a partly-terraformed planet where they have become the dominant species. Once again, Corvid intelligence is qualitatively different than that of human beings and other species in the previous novels. The Corvids are able to speak, but their intellectual activity happens, not in individual birds, but only in pairs. One member of a pair gathers information, parses patterns in the information, and especially notices instances of novelty. The other member of the pair in effect collates this information and strategizes ways to act upon it. Neither of the pair can do much on its own; but in conjunction, the pairs are able to analyze large reams of data and operate complex technology. Whether they are capable of originality (as opposed to noticing and moblizing novelties that they discover in their environment) is uncertain. The Corvids deny that they are sentient; the actual situation seems to be that sentience inheres in their combined operations, but does not quite exist in either of their brains taken separately. In certain ways, the Corvids in the novel remind me of current AI inventions such as ChatGPT; they emit sentences that are insightful, and quote bits and fragments of human discourse and culture in ways that are entirely apt; but (as with our current level of AI) it is not certain that they actually “understand” what they are doing and saying (of course this depends in part on how we define understanding). Children of Memory is powerful in the way that it raises questions of this sort — ones that are very much apropos in the actual world in terms of the powers and effects of the latest AI — but rejects simplistic pro- and con- answers alike, and instead shows us the difficulty and range of such questions. At one point the Corvids remark that “we know that we don’t think,” and suggests that other organisms’ self-attribution of sentience is nothing more than “a simulation.” But of course, how can you know you do not think without thinking this? and what is the distinction between a powerful simulation and that which it is simulating? None of these questions have obvious answers; the novel gives a better account of their complexity than the other, more straightforward arguments about them have done. (Which is, as far as I am concerned, another example of the speculative heft of science fiction; the questions are posed in such a manner that they resist philosophical resolution, but continue to resonate in their difficulty).

The dilemma of the Corvids and their degree (or not) of sentience is encased within a much broader story or unsuccessful terraforming, or of the mismatch between human organisms and their re-created environment. The novel mostly takes place on and around a planet that has been only incompletely terraformed; thousands of years later, a generation starship containing thousands of human beings in cryonic suspension arrives with the mission to found a new society on this planet. The attempt is tragically unsuccessful, for a number of reasons. I don’t want to give away all the plot twists here, so I will just say that the novel envisions a series of interactions between Earth-born colonists and their descendants and an unforgiving environment that only includes a limited number of transplanted Earth species, as well as these baseline humans’ interactions with the various transformed species (including but not limited to human beings who have themselves been boosted by their encounters with the other intelligent species and with the advanced technologies arising from their encounters), and also with an even more powerful technology left behind by an unknown alien species. There are multiple levels of simulation and speculation, as well as even more complex and self-reflexive levels of both intelligence and sentience (with the relation between these never becoming entirely certain). There is a lot here that deserves unpacking at much greater length than I am capable of, after writing this brief review from just one reading. The entire Children series, and this third volume in particular, exemplifies how science fictional fabulation, at its best, can lead us to reflect upon vital issues in ways that simplistic pro- and con- arguments are unable to do.