A sandbox reference for Atmaverse contributors who are here for the weird aliens and want to understand the political scaffolding.
Before reading any of this, go play Nicky Case's The Evolution of Trust. It's interactive, it takes about 30 minutes, and it teaches the core concepts below better than any written explanation can. Everything on this page will make more sense afterward.
The Atmaverse federation isn't held together by goodwill, shared values, or a universal moral code. It's held together by structure - specifically, by the fact that its member species can sustain long-term cooperative relationships where everyone benefits. Species #0 is the boundary of that structure: not "the bad guys," but species whose cognitive architecture makes stable cooperation structurally impossible. If you're designing a species for the setting, you need to understand where that boundary is and how your species relates to it.
The good news is that you don't need a game theory textbook. You need about five concepts.
This is the single most important distinction in the entire framework.
A one-shot game is an interaction where you'll never see the other party again. There are no future consequences, no reputation effects, no possibility of retaliation. In a one-shot game, screwing the other party over ("defecting") is often the rational move, because you get the benefit and pay no long-term cost.
An iterated game is an interaction where you'll deal with this party again and again, indefinitely. Now defection has consequences: the other party remembers what you did, and they'll adjust their behavior accordingly. Cooperate, and they'll cooperate back. Defect, and they'll retaliate, and you've poisoned the well for all future interactions. In iterated games, cooperation becomes the rational strategy even for purely self-interested actors, because the long-term benefits of a sustained cooperative relationship outweigh the short-term gains of defection.
The federation is a framework for iterated games between species. Member species interact repeatedly, over long timescales, with reputations that carry across those interactions. That's what makes cooperation stable - not friendship, not altruism, just the structure of repeated interaction with memory.
For your species: Think about whether your species can play iterated games. Can they recognize other players across repeated interactions? Can they track reputation (who cooperated, who defected)? Do they care about future outcomes, or are they so present-focused that long-term consequences don't register? These are the structural questions that determine federation compatibility.
This is the point that trips up most people coming from a humanities or biology background. Federation species don't cooperate because they're nice. They cooperate because, given the structure of iterated interactions with reputation tracking and the possibility of retaliation, cooperation is the strategy that maximizes long-term outcomes for each party.
You can be entirely selfish and still end up cooperating, as long as the game is structured so that cooperation pays better than defection over time. The federation doesn't care why you cooperate - whether it's because you genuinely value others' wellbeing, because your biology makes defection impossible, because you've calculated that it's optimal, or because you're terrified of retaliation. It only cares that you can sustain cooperation reliably.
The existing species illustrate the full spectrum of cooperative motivation:
Weavers cooperate because their deepest communication mode - engram exchange, literally ingesting and integrating another's cognitive patterns - dissolves disagreement from the inside. You can't sustain defection against someone whose reasoning is running inside your own mind. Their cooperation is enforced by cognitive integration.
Ansale'wit cooperate through a different kind of involuntary transparency - their cognition generates electromagnetic fields that other ansale'wit perceive directly. The decision to be private is itself public information, because the effort of signal dampening is visible. Their cooperation is enforced by the physics of their cognitive architecture.
Apocritans cooperate externally because the federation's payoff structure makes cooperation the dominant strategy. They are explicit about this. Their official position is essentially: we are in the federation because it is useful to be in the federation. The field guide editorial board noted, with some tartness, that this is "a more honest posture than that adopted by some federation members who claim prosocial motivations while behaving instrumentally."
Humans cooperate because they learned to, slowly and imperfectly, through institutional development, cultural norms, and painful trial and error, without any biological enforcement mechanism. Humans can lie with their faces, mask their emotions, and defect without anyone knowing - and they built cooperative civilization anyway, through inference, guesswork, language, and trust. To species with involuntary transparency, this is either miraculous or insane.
Each species arrives at cooperation through a completely different mechanism. The federation accommodates all of them. That's the point: cooperation is a strategy, not a value, and the framework is agnostic about the underlying machinery.
A species #0 is not a villain. It is not "the evil species." It is a species whose cognitive architecture, utility function, or social structure means the conditions for stable iterated cooperation cannot be met. The federation doesn't hate species #0s - it simply can't incorporate them, the same way you can't play chess with someone who's playing a fundamentally different game.
A species qualifies as #0 when one or more of the following structural conditions hold, and the condition is inherent to the species rather than circumstantial:
They always defect. Their utility function is structured so that defection is always optimal regardless of what the other party does. This could be because their reward circuitry is wired so that others' suffering is intrinsically rewarding (zero-sum or negative-sum cognition), or because they genuinely cannot benefit from mutual cooperation the way the interaction is structured. No amount of goodwill or diplomacy changes the math - cooperating with them always costs you and always benefits them at your expense.
They can't sustain iteration. Maybe they lack persistent identity, so reputation tracking is impossible (you can't retaliate against a defector if you can't identify them next time). Maybe they're so cognitively short-term that future consequences literally don't factor into their decision-making. Maybe their social structure reorganizes so frequently that commitments made by one configuration aren't honored by the next. The iterated game requires continuity of some kind, and they don't have it.
They can't be deterred. Iterated cooperation is partly sustained by the threat of retaliation - if you defect, I'll defect back, and we both lose. If a species genuinely doesn't care about retaliation (because they're individually disposable, or because their utility function doesn't penalize mutual defection, or because they're cognitively incapable of modeling the consequences), then the mechanism that sustains cooperation breaks down.
The critical thing to understand is that species #0 is a structural category, not a moral or social one. A species can be friendly, communicative, even individually likable, and still be species #0 if their underlying utility function makes stable cooperation impossible. Conversely, a species can be aggressive, antisocial, and deeply unpleasant while being perfectly federation-compatible, because their utility function does permit positive-sum outcomes even if their temperament makes achieving those outcomes a headache.
Two illustrative cases. The Listener larvae are intelligent, capable of problem-solving and tool use, individually impressive animals. But they are constitutionally incapable of sustained cooperation - their cognition is optimized for competition, resource hoarding, and short-term gain. If they were spacefaring, they'd be species #0. They aren't, because they can't cooperate long enough to build a spacecraft, which is its own kind of safeguard.
The species that colonized the ansale'wit homeworld of Regez is a different kind of illustration. They arrived, found a planet rich in minerals and geothermal energy, and began extraction - destroying sections of the planetary fungal network that was the ansale'wit civilization. At first, this was nonmalicious. They didn't recognize a planetary fungal network as sapient. When the ansale'wit began fighting back, the colonizers turned hostile. The species #0 classification here isn't about intent - it's about structural incompatibility. The colonizers may have been perfectly capable of cooperation with species they recognized as persons. They just couldn't recognize these persons, and by the time they did, they'd already committed to extraction. Sometimes the incompatibility is perceptual before it's strategic.
The federation is a structure for managing inter-species iterated games. What a species does internally - to its own members - is outside that structure's scope. This is the "space NATO, not space CIA" principle: the federation enforces cooperative norms between member species but does not intervene in internal affairs.
This is a practical constraint, not a moral endorsement. Other federation members can express disapproval through soft power, cultural pressure, diplomatic leverage, trade incentives, and loud public argument. They cannot use force to change another species' internal practices. The line is external behavior: as long as you cooperate reliably with other federation species, your internal social structure is your own business, however repugnant other members find it.
The apocritans are the sharpest test case. Their hive queens control caste determination through nursery chemistry, maintain social cohesion through pheromones embedded in the food supply, and enforce reproductive monopoly through the execution of unauthorized drones. Synthetic pheromone-free food exists and is technologically feasible; queens suppress its production. Workers' neurochemistry has been shaped from their first adult meal to experience the queen's authority as natural - the control operates below the level of conscious deliberation. From the workers' subjective perspective, they aren't being coerced. They're just living in the world as it is.
Different federation species object to this on different grounds, and the differences are revealing. Humans object on autonomy grounds: the drones can't choose. The ansale'wit object on identity grounds: shaping someone's neurochemistry without their knowledge constitutes a kind of identity violation. The Weavers - and this is the uncomfortable part - don't object much at all, because from a pattern-continuity perspective the workers' patterns are being maintained, just within a shaped environment. Each objection follows from the objecting species' own identity model and cooperation mechanism. The federation as a structure does none of these things. The apocritans cooperate reliably with external partners, and their internal practices are classified as an internal matter.
The ansale'wit homecoming debate illustrates a less dramatic but equally important application of the principle. The question of whether the diaspora should return to Regez or embrace their shipboard identities is a genuine political division with no clear right answer. The federation has no business weighing in. The principle isn't only about tolerating harm - it's about respecting that a species' internal questions are theirs to resolve.
For your species: If you want to design a species with troubling internal practices, the federation framework supports that - the interesting question becomes how other species react to it through soft power rather than force. The richest inter-species tensions in Atmaverse come from this dynamic: "we can't make you stop, but we can make it very clear how we feel about it, and we can structure our trade agreements accordingly." And the most interesting cases are the ones where the objecting species recognizes something of its own practices in the thing it's condemning.
This concept isn't in most game theory primers, but it's central to Atmaverse. A species can be perfectly cooperative, genuinely benevolent, and still cause enormous harm by universalizing its own model of cooperation without understanding that other species' cooperation works differently.
The Weavers are the defining example. Their internal cooperation mechanism is engram exchange - deep cognitive integration where disagreements dissolve because you can think the other person's thoughts from the inside. Within their own species, this produces extraordinarily stable, deeply trusting social structures. It also produces the Atma program: the decision to preserve pre-spacefaring species by dissolving their populations, archiving their cognitive patterns as pearls, and reconstituting them into rebuilt environments. The Atma program is Sex 1 - the thing Weavers do for the people they love most - scaled up to civilizations. From inside Weaver psychology, it is the most generous thing they have ever done.
From inside human psychology, it is the most violating. The Weavers' error, to the extent they made one, was not malice but universalization. They assumed that pattern-continuity means the same thing to species that didn't evolve the pearl mechanism as it does to species that did. They extended their own cooperation model - "we carry your pearl, we hold you safe, we restore you when conditions allow" - without fully grasping that other species might experience being carried as being consumed.
Every species' objection to Atma - should they have one - follows from its own identity model, and no two objections are quite the same. The ansale'wit say: preserving individuals while severing their connections is not preservation, it is a specific form of destruction that leaves the victims alive to experience what was taken. The apocritans say: the error was reconstituting archived individuals into unaugmented biological bodies instead of providing fully mechanical interfaces - not the archival, not the dissolution, but the failure to upgrade. Humans say: we didn't consent, and we can't determine whether the pearl state constituted a continuity of our consciousness or a sufficiently precise simulation of one, and that uncertainty is itself a harm.
For your species: Think about what your species would do with overwhelming power and genuinely good intentions. The answer reveals their deepest assumptions about what other beings need, and those assumptions are where the most interesting inter-species conflicts live. The Weavers didn't set out to violate anyone. They set out to save everyone, using the only framework they had for understanding what "saving" means.
When creating a species for Atmaverse, you don't need to formally model their game theory. But it helps to ask yourself these questions:
How does your species cooperate? What mechanism makes cooperation sustainable for them? The existing species cover a remarkable range: biologically enforced transparency (ansale'wit), cognitive integration (Weavers), instrumental calculation (apocritans), learned institutional norms without biological enforcement (humans). Your species needs its own answer, and the answer should follow from its biology rather than being stapled on.
What are their failure modes? Under what conditions does cooperation break down for your species? For humans, it's desperation: when survival is at stake, cooperative norms collapse. For the ansale'wit, it's signal starvation: network disconnection that dulls cognition and degrades social processing. For the apocritans, it's resource scarcity: a hive that can't feed its workers can't maintain the pheromone-mediated social structure that keeps cooperation stable. Knowing your species' failure mode tells you where the interesting stories are.
Where do they sit relative to the species #0 boundary? The most compelling species aren't the ones that cooperate perfectly (boring) or defect completely (they can't be in the setting). They're the ones where the answer is complicated - species that can cooperate but find it difficult, or species whose cooperation depends on specific conditions that might not always hold, or species where some internal faction is pushing toward the #0 boundary while others pull back.
What's their relationship to the Atma question? Every species has a perspective on it, shaped by their own cognitive architecture and values. Your species doesn't need to have a definitive answer, but they should have a reaction - and that reaction should follow from their biology and game-theoretic position rather than being imposed from outside.
Conflating "antisocial" with "all-defect." A species that's aggressive, territorial, and unpleasant to deal with is not necessarily species #0. The apocritans are competitive, frequently hostile between hives, and explicitly instrumental in their federation participation - and they're perfectly valid members, because their utility function permits positive-sum outcomes even when their temperament doesn't suggest it. Species #0 means the math doesn't work, not that the vibes are bad.
Making species #0 into cartoon villains. Species #0 isn't an alignment. It's a structural incompatibility. The species that colonized Regez may have had rich internal culture and genuine individual virtue - they just couldn't recognize a planetary fungal network as a person, and that perceptual failure made cooperation impossible regardless of intention. The problem isn't evil. It's incompatibility.
Assuming cooperation requires liking each other. Some of the most productive federation relationships are between species that find each other mutually incomprehensible or actively distasteful but cooperate anyway because the iterated game makes it worthwhile. Human-apocritan relations are "primarily economic and conducted primarily at the working level" - engineers, traders, soldiers getting along fine while institutions remain in fundamental tension. Cooperation is a strategy, not a feeling.
Assuming cooperation requires shared values. The federation accommodates species whose cooperation is morally motivated (ansale'wit), instrumentally calculated (apocritans), and culturally learned (humans). It accommodates species that locate identity in pattern (Weavers), in relational expression (ansale'wit), in subjective continuity (humans), and in the process of self-construction (apocritans). No shared values are required. Shared structure is required: the ability to play iterated positive-sum games reliably, regardless of why.
Forgetting that the federation is a structure, not a government. The federation doesn't legislate, doesn't enforce internal policy, and doesn't have a president. It's a framework that makes inter-species cooperation stable. The soft-power dynamics - trade leverage, cultural pressure, support for reform factions - are conducted by member species acting in their own interests within the framework, not by the framework itself.