❶ The Question
How do microscopic variations — random fluctuations, individual differences, diverse components — give rise to macroscopic order? And conversely, when does variation destroy order rather than create it?
Consider an orchestra. Every musician is different: different instruments, different timbres, different physical positions on stage, slightly different interpretations of the score. This variation is not a defect to be eliminated — it is precisely what gives the orchestra its richness. A hundred identical synthesizers playing the same note would produce volume, not music. But variation alone is not enough either. A hundred musicians each playing whatever they feel like produces cacophony, not a symphony. The interesting regime — the one where something remarkable happens — is when diverse components vary and coordinate: each musician contributes something different, and yet all of them play together.
ECI calls this the Coordinated Diversity regime: the condition where a system has high variation (V) and high coordination (kappa) simultaneously. This page develops that concept, examines what established science tells us about the relationship between variation and coordination, and proposes — as an ECI hypothesis, not an established law — that the most capable systems operate in this regime.
❷ The Observation
Three regimes
Start with three contrasting systems and ask: how much variation do they have, and how coordinated are they?
White noise — a signal where each sample is drawn independently from some probability distribution with no correlation between successive values. White noise has high variation — it explores its state space freely, with no pattern repeated — but essentially zero coordination. Each sample is statistically independent of every other. If you are listening to white noise, knowing the current sample tells you nothing about the next one. High V, low kappa.
A perfect crystal — say, a single crystal of silicon at low temperature. Every atom sits at a precise lattice position. The structure is exquisitely ordered, perfectly predictable, and almost entirely uniform. The crystal has very low variation — once you know the lattice parameters, you know where every atom is — and very high structural regularity. But this "coordination" is trivial: the atoms are not doing anything together in any dynamic sense. They are simply frozen in place. Low V, high structural regularity but static. The crystal has order without diversity.
A working brain — say, the neocortex of a human engaged in a complex task. Billions of neurons, each with its own firing characteristics, its own synaptic connections, its own position in the network. The variation is enormous: no two neurons behave identically, firing patterns are irregular when viewed individually, and the system operates far from any simple periodic or crystalline state. But this variation is not random — it is profoundly coordinated. Neurons form transient coalitions, synchronize across distant brain regions, create oscillatory patterns at multiple frequencies, and maintain coherent representations that last long enough to guide behavior. If you measure the brain's signals with an EEG, you see neither white noise nor a monotone — you see structured, dynamic, coordinated complexity. High V and high kappa.
The brain is doing something that neither white noise nor a crystal can do: it combines diversity and coordination. Each neuron contributes something different, and yet the whole system acts coherently. This is the Coordinated Diversity regime.
Why this matters
The contrast between these three regimes is not merely a classification exercise. It points to a deep question: what mechanisms allow a system to be both diverse and coherent? White noise shows that variation without coordination produces nothing usable. A crystal shows that order without variation produces nothing flexible. The brain — and by extension, many other complex systems from ecosystems to economies — shows that something qualitatively different emerges when variation and coordination coexist at high levels.
ECI proposes that this "something different" is not accidental. It reflects a fundamental relationship between variation (V) and coordination (kappa) that governs what any system can achieve.
❸ What We Already Know
Several well-established results from different fields illuminate the relationship between variation, complexity, and coordination.
May (1972): Complexity does not automatically produce stability. Robert May's landmark paper "Will a Large Complex System Be Stable?" examined the stability of randomly assembled ecological communities. Using random matrix theory, he analyzed model ecosystems where species interact with random interaction strengths. His central result: in a randomly assembled community of S species, where each pair interacts with probability C (connectance) and the interaction strengths are drawn from a distribution with standard deviation sigma, the system transitions from stable to unstable when sigma * sqrt(S * C) exceeds a critical threshold (approximately 1).
The implication is profound and often misunderstood. May's result is a warning that "more complexity" does not monotonically imply greater stability; interaction architecture matters. A system that simply adds more species with more connections and stronger interactions will, in the random interaction model, become less stable, not more. Real ecosystems are more stable than random-matrix predictions because they are not randomly assembled — they have been shaped by evolution, which prunes unstable configurations and favors interaction architectures that promote persistence. The stability of real ecological networks arises not from complexity per se but from the structure of complexity: which species interact with which, how strongly, and in what configuration.
For ECI, May's result supports a central claim of this page: variation alone is not enough. A system that simply increases V (more diverse components, more connections, stronger interactions) without attending to how those components are coordinated will not necessarily become more capable or stable. Coordination — the architecture of interactions — is what converts variation from a liability into an asset.
Stochastic resonance: noise can help, under specific conditions. Beginning with Benzi, Sutera, and Vulpiani (1981), and confirmed across numerous experimental systems (electronic circuits, sensory neurons, human perception), researchers have demonstrated that in certain nonlinear systems, appropriate noise can improve weak signal detection — a phenomenon called stochastic resonance.
The mechanism requires specific conditions: (1) a nonlinear system with a threshold or bistability, (2) a signal that is too weak to drive the system past the threshold on its own (subthreshold), and (3) noise of appropriate intensity. Under these conditions, the noise intermittently pushes the system past the threshold in synchrony with the weak signal, producing output that tracks the signal better than in the absence of noise. The relationship between noise intensity and signal detection is non-monotonic: too little noise fails to boost the signal, too much noise overwhelms it, and there is an optimal intermediate level. Reviews by Gammaitoni et al. (1998), Moss et al. (2004), and McDonnell and Ward (2011) cover the theory and experimental evidence.
Stochastic resonance is not a general law that "noise improves signals." It has specific dynamical prerequisites that many systems do not meet. Its importance here is as a concrete, well-studied example of a non-monotonic relationship between variation (noise, in this case) and system performance (signal detection). It demonstrates that there can be an optimal level of variation — and that this optimal level depends on the system's architecture.
Complex systems literature: the edge of chaos. Kauffman (1993) studied random Boolean networks and found that networks in a "critical" regime — between frozen (ordered) and chaotic — showed the most complex, computationally interesting dynamics. Langton (1990) proposed the related "edge of chaos" concept. Bak, Tang, and Wiesenfeld (1987) showed that many systems self-organize to a critical state (self-organized criticality). These results, from different mathematical frameworks, converge on a similar insight: the most interesting dynamics — the most computational capacity, the most adaptive flexibility — often emerge at an intermediate regime, not at the extremes of order or disorder.
Kuramoto model: synchronization as a phase transition. Kuramoto (1975, 1984) showed that a population of oscillators with different natural frequencies (variation) will spontaneously synchronize (coordination) when coupling strength exceeds a critical threshold. Below the threshold, each oscillator runs independently; above it, a macroscopic fraction locks into a common frequency. This is a clean mathematical demonstration that coordination emerges from variation through coupling — and that the transition is sharp, not gradual.
What these results collectively show: Variation and coordination are not independent properties that systems happen to have in different amounts. They interact in complex, often non-monotonic ways. More variation does not automatically improve systems (May). Appropriate variation can enhance performance under specific architectural conditions (stochastic resonance). The most capable regimes often lie between order and disorder (edge of chaos, criticality). Coordination can emerge from variation through coupling mechanisms (Kuramoto). These are established results. What they do not provide is a unified framework relating V and kappa across domains — that is the gap ECI addresses.
❹ The Framework Interpretation
V as a Family of Variation Measures
ECI uses V to refer to the variation in a system — but a critical clarification is necessary.
ECI currently uses V as a family of variation measures rather than a single universal scalar. The "variation" of a system can be quantified in many different ways, and these different measures are not interchangeable:
- Statistical variance: the spread of a distribution around its mean. Appropriate for continuous numerical variables.
- Shannon entropy: the average information content per symbol in a message or state distribution. Measures uncertainty or diversity of states.
- State-space occupancy: the fraction of possible states a system actually visits over a given time window. Captures how much of its potential repertoire a system uses.
- Temporal fluctuation: how rapidly and irregularly a system's state changes over time.
- Spatial heterogeneity: how different the system's components are from each other at a given moment.
- Behavioral diversity: the number and variety of distinct behavioral patterns a system can produce.
These measures can dissociate dramatically. A system can have low statistical variance but high Shannon entropy (a discrete system visiting many states, each with similar probability, but within a narrow numerical range). A system can have high temporal fluctuation but low state-space occupancy (oscillating rapidly between just two states). A system can have high spatial heterogeneity but low behavioral diversity (many different components, each doing the same thing).
For any specific system under study, the researcher must choose which dimension(s) of V are relevant and state that choice explicitly. Claiming "this system has high V" without specifying which measure is meaningless.
The ECI framework treats V as a family rather than collapsing these measures into a single number. Whether a principled unification is possible — some master measure from which the others derive — is an open question. For now, V is a placeholder for the appropriate variation measure in context, and any ECI analysis must specify which V is being used.
kappa: The Coordination Parameter
Where V measures how different a system's components are, kappa measures how coordinated they are — how much the behavior of one component constrains or predicts the behavior of others.
Like V, kappa can be operationalized in multiple ways depending on the system:
- Phase coherence in oscillator populations (proportion of oscillators locked to a common phase)
- Mutual information between components (how much knowing one component tells you about another)
- Global order parameters (magnetization in spin systems, alignment in flocking models)
- Functional connectivity (correlation structure across components)
- Collective behavioral coherence (degree to which a group acts as a unit)
Low kappa means components act independently — knowing one tells you little about the others. High kappa means strong interdependence — the components are tightly coupled and their behaviors are mutually constrained.
The V-kappa Plane
The two measures V and kappa define a conceptual plane on which different systems can be located:
| | Low kappa (uncoordinated) | High kappa (coordinated) | |---|---|---| | High V (diverse) | White noise, ideal gas, random network | Coordinated Diversity: brain, ecosystem, jazz ensemble | | Low V (uniform) | Dead system, empty space | Crystal, rigid lattice, marching band in unison |
The four corners:
- Low V, low kappa: Nothing interesting happens. No diversity, no coordination. An inert, featureless system.
- Low V, high kappa: Rigid order. Perfect regularity, but no flexibility, no adaptability, no computational capacity. A crystal. A marching band playing a single note in perfect unison.
- High V, low kappa: Random variation. Lots of diversity, but none of it organized. White noise. An orchestra where every musician plays a different piece simultaneously.
- High V, high kappa: Coordinated Diversity. The components are diverse and they work together. Each contributes something different, and the differences are organized into a coherent whole. A working brain. A healthy ecosystem. A jazz ensemble. An adaptive immune system.
ECI proposes that the upper-right quadrant — high V, high kappa — is where the most capable, adaptive, and computationally rich systems operate. This is not a claim that all systems should maximize both V and kappa (there may be good reasons for a system to operate in other quadrants), but that the systems we find most interesting — brains, ecosystems, economies, adaptive organizations — tend to live in this regime.
The Optimal V* Hypothesis
ECI proposes that for a given system with a given coordination architecture, there exists an optimal level of variation V* — a level that balances two competing demands:
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V too low: the system lacks coverage. Its components are too similar, exploring too little of the state space. It cannot adapt to novel conditions because it has no diverse repertoire to draw from. A population of genetically identical organisms is exquisitely vulnerable to a single pathogen. A portfolio of identical investments is maximally exposed to a single market shift.
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V too high: the system loses coherence and retention. Its components are so different that coordination becomes impossible — the coupling mechanisms cannot bind them into a functioning whole. Patterns cannot persist because they are constantly disrupted by uncorrelated fluctuation. An orchestra where each musician plays in a random key at a random tempo cannot produce music regardless of the musicians' individual skill.
The relationship between V and system performance is therefore non-monotonic: increasing V improves performance up to a point, then degrades it. The optimal V* depends on the system's coordination architecture (kappa), its coupling mechanisms (Gamma), its capacity (K), and the demands of its environment.
This is an ECI hypothesis, not an established law. It is motivated by analogy to stochastic resonance (non-monotonic noise-performance relationship), May's stability result (more complexity can reduce stability), and the edge-of-chaos literature (intermediate regimes are often optimal). But none of these established results directly proves the existence of a universal V* across all system types. The hypothesis requires testing in specific systems before it can be elevated to a general claim.
Coordinated Diversity: The Interesting Regime
Bringing V and kappa together, ECI proposes that the regime of greatest interest is Coordinated Variation (or Coordinated Diversity): high V combined with high kappa.
In this regime:
- The system has a rich repertoire of diverse components (high V), giving it coverage — the ability to match a wide range of environmental demands.
- The system's components are coordinated (high kappa), giving it coherence — the ability to act as a unified whole, maintain persistent patterns, and produce organized outputs.
- The coordination does not suppress the variation — it organizes it. Each component retains its distinctiveness while contributing to a collective pattern.
The orchestra analogy captures this well. The violins sound different from the cellos, which sound different from the oboes, which sound different from the timpani. This variation is the point — it is what gives the orchestra its harmonic richness, its range of expression, its ability to produce sounds that no single instrument could. But the variation is coordinated by a shared score, a shared tempo, a shared tonal center, and the real-time adjustments of the conductor and the musicians' mutual listening. The result is not a compromise between variation and coordination but an enhancement of both: the variation enables richer coordination, and the coordination enables productive variation.
❺ If This Were True...
If the V-kappa framework correctly captures a fundamental relationship between variation and coordination, several design implications follow.
System design becomes a balancing act. Engineers, policymakers, and organizational designers would need to attend explicitly to both V and kappa, not just one. A team that seeks innovation should not simply hire diverse people (increasing V) — it must also build communication structures, shared goals, and collaboration norms (increasing kappa) that allow the diversity to be coordinated. Conversely, a team that seeks reliability should not simply enforce uniformity (reducing V) — it may lose the adaptive capacity that diversity provides.
Diagnostic power. If a system is performing poorly, the V-kappa framework suggests two distinct failure modes to check. Is V too low? (The system lacks the diversity to cover its environment.) Is kappa too low? (The system has diversity but cannot coordinate it.) Or is V too high? (The system has so much uncoordinated variation that coherence is lost.) Each diagnosis leads to a different intervention.
Evolutionary interpretation. Natural selection may be understood, in part, as a mechanism that pushes populations toward the Coordinated Diversity regime. Mutation and recombination generate variation (increasing V). Selection and genetic drift eliminate some variants (shaping V). Social behavior, signaling, symbiosis, and ecological interactions create coordination among organisms (building kappa). Ecosystems that persist over evolutionary time are those that maintain enough V for adaptation and enough kappa for functional coherence.
Fragility predictions. Systems in the Coordinated Diversity regime may be fragile in specific, predictable ways: disruptions that reduce kappa while V remains high (destroying coordination without reducing diversity) should cause particularly rapid degradation — the system collapses from organized complexity to mere noise. An ecosystem that loses its keystone species (a coordination hub) while retaining its species diversity might exhibit this pattern: the species are still there, but the functional organization is gone.
These are extrapolations. Their value depends entirely on whether the V-kappa framework generates predictions that survive empirical testing.
❻ How Could We Test It?
The Variation & Coordination framework makes several testable claims, each requiring different experimental approaches.
Test 1: Agent-based models manipulating V and kappa independently. Build agent-based simulations where V and kappa can be controlled as independent variables. For example: a population of agents, each with a strategy drawn from a strategy pool (V controls the diversity of the pool), interacting on a network (kappa controls the coupling structure). Measure collective performance — resource harvesting, problem-solving, survival — across a matrix of (V, kappa) values. The framework predicts: (a) the best performance occurs at high V and high kappa jointly, (b) the relationship between V and performance is non-monotonic (inverted-U) for any fixed kappa, and (c) the optimal V* shifts depending on kappa. If performance depends only on V, or only on kappa, or increases monotonically with both, the framework fails.
Test 2: Empirical V-kappa mapping across real systems. Select well-characterized systems from diverse domains — neural networks (functional connectivity data), ecosystems (species interaction networks), economic networks (trade data), social groups (communication networks). For each, independently measure V (using appropriate variation metrics for the domain) and kappa (using appropriate coordination metrics). Map the systems onto the V-kappa plane. The framework predicts that the most functional, adaptive, and persistent systems cluster in the high-V, high-kappa quadrant. If the most successful systems are distributed uniformly across the plane, the framework adds no predictive value.
Test 3: Non-monotonic V in controlled systems.* In a system where V can be experimentally manipulated — such as the diversity of strains in a microbial community, the heterogeneity of components in an electronic network, or the diversity of agents in a simulation — increase V from low to high while keeping kappa constant. Measure system performance at each level. The framework predicts a non-monotonic relationship: performance improves with V up to some V*, then declines. If the relationship is monotonically increasing or monotonically decreasing across all tested systems, the V* hypothesis is falsified for those systems.
Test 4: Coordination collapse. In a system operating in the high-V, high-kappa regime, selectively disrupt coordination mechanisms while preserving diversity. The framework predicts that kappa reduction at high V causes more severe degradation than kappa reduction at low V — because the uncoordinated diversity becomes actively destructive rather than merely inert. In neural systems, this might be tested pharmacologically (disrupting synchronization while preserving individual neuron firing properties). In ecological systems, this might be tested by removing keystone species (coordination hubs) while maintaining species diversity.
What would weaken this claim: If V and kappa do not predict system performance better than simpler single-variable models (e.g., just network density, just species richness, just coupling strength alone).
What would kill this claim: If the most capable, adaptive systems across multiple domains are consistently found at low V or low kappa — i.e., if the Coordinated Diversity regime is not empirically associated with the properties ECI attributes to it.
❼ Connected Nodes
→ ECI Unit: The minimal dynamic unit of Information, Carrier, and Energy. Variation and coordination are properties of populations of ECI units — the diversity (V) of the Information Vectors, Carriers, and Energy flows present, and the degree of coordination (kappa) among them. A single ECI unit has no V in isolation; V is inherently a collective property.
→ Coupling & Resonance (B5): Coupling (Gamma) is the mechanism through which coordination (kappa) arises. Without coupling between components, variation remains local and uncoordinated — the system stays in the high-V, low-kappa quadrant. B5 develops the formal machinery; C1 describes what happens when that machinery produces coordination at scale.
→ Persistence Filtering (C2): Persistence filtering is the temporal dimension of coordination — patterns that are coordinated enough to maintain themselves over time are "filtered in" and persist, while uncoordinated patterns dissolve. The stability term in the A_access equation connects directly to C2's treatment of what persists and why.
→ Emergence & Scale (C4): Emergence is what happens when coordinated diversity produces macroscopic patterns that are not predictable from individual components alone. C4 asks how scale transitions work; C1 provides the raw materials (V and kappa) whose interaction drives those transitions.
→ Evolutionary Filtering (C5): Evolution is a mechanism that shapes V and kappa over time — mutation and recombination generate variation, selection prunes it, and ecological and social interactions build coordination. The V-kappa framework provides a lens for understanding what evolution is optimizing.
❽ Mathematical Detail
V: Variation Measures (Family Definition)
V denotes a family of measures quantifying the variation, diversity, or heterogeneity within a system. The choice of measure depends on the system and the question:
| Measure | Notation | Definition | Appropriate for | |---|---|---|---| | Statistical variance | V_var | E[(X - mu)^2] for random variable X with mean mu | Continuous numerical variables | | Shannon entropy | V_H | -sum_i p_i log p_i over state probabilities p_i | Discrete state distributions | | State-space occupancy | V_occ | |visited states| / |possible states| over time window T | Systems with discrete, enumerable states | | Temporal fluctuation | V_temp | Rate and irregularity of state changes over time | Time-series data | | Spatial heterogeneity | V_spat | Variance or entropy across spatial positions at a given time | Spatially distributed systems | | Behavioral diversity | V_beh | Number and variety of distinct behavioral patterns | Ethological and organizational systems |
- Status: Definitions (measurement conventions). The list is not exhaustive.
- Critical assumption: These measures are NOT generally interchangeable. A claim about one V measure does not automatically transfer to another. Any ECI analysis using V must specify which measure(s) are employed.
kappa: Coordination Parameter
kappa measures the degree of coordination among a system's components — the extent to which the state of one component constrains or predicts the states of others.
Possible operationalizations include:
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Phase coherence (Kuramoto order parameter): kappa =
|1/N sum_j exp(i * theta_j)| -
Mean pairwise mutual information: kappa =
(2 / N(N-1)) sum_{i<j} MI(X_i; X_j) -
Global order parameter (domain-specific)
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Functional connectivity (thresholded correlation matrix density)
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Status: Proposed definition (framework variable).
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Assumptions: That coordination across diverse systems can be meaningfully quantified; that a scalar kappa captures the essential feature for a given system type.
Toy Model: Coverage Formula
Consider a system of N diverse components, each of which independently has probability q of matching a given environmental demand. The probability that at least one component provides a match is:
P(match >= 1) = 1 - (1 - q)^N
This is a toy model assuming:
- Independence — each component's match probability is independent of the others. In real systems, components are typically correlated (nearby neurons co-fire, neighboring species share niches, connected agents influence each other).
- Constant q — the match probability is the same for all components. In heterogeneous systems, q varies across components.
- Binary matching — a component either matches or it does not. Real compatibility is continuous (the Q function from B5).
Under these (unrealistic) assumptions, the model illustrates that increasing N (more diverse components, i.e., higher V) increases coverage — the probability that the system can match an environmental demand. For q = 0.01: at N = 50, P is approximately 0.395; at N = 100, P is approximately 0.634; at N = 500, P is approximately 0.993.
- Status: Toy model. Not proposed as a description of real systems. Useful only for illustrating the coverage benefit of variation under idealized conditions.
- Limitation: The model captures the benefit of V (coverage) but not the cost (loss of coherence at high V). A complete model must include kappa-dependent terms.
Proposed Equation: Accessible Coordination
ECI proposes that the accessible coordination of a system — the degree to which coordinated activity can be sustained — depends jointly on coverage (from variation) and coordination readiness:
A_accessapprox [1 - (1 - q)^N] x R(kappa, K, stability)
where:
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[1 - (1 - q)^N] is the coverage term from the toy model above (with all its limitations)
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R(kappa, K, stability) is a coordination readiness function depending on:
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Status: Proposed equation. The functional form of R is not specified. The multiplicative decomposition into coverage and readiness is a working assumption, not a derived result.
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Assumptions: That accessible coordination can be separated into a "having diverse components available" factor and a "being able to coordinate them" factor; that these factors are approximately multiplicative (i.e., roughly independent). Both assumptions need empirical validation.
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Falsifiable consequence: If
A_accessdoes not predict observed coordination outcomes better than simpler single-variable measures, the equation should be revised or abandoned.
Summary of Notation
| Symbol | Name | Type | Defined in |
|---|---|---|---|
| V | Variation (family) | Family of measures | This page |
| V_var, V_H, V_occ, V_temp, V_spat, V_beh | Specific variation measures | Definitions | This page |
| kappa | Coordination parameter | Proposed definition | This page |
| V* | Optimal variation level | ECI hypothesis | This page |
| P(match >= 1) | Coverage probability | Toy model | This page |
| A_access | Accessible coordination | Proposed equation | This page; B5 |
| Q | Compatibility function | Proposed definition | B5 |
| Gamma | Coupling function | Proposed definition | B5 |
| K | Carrier capacity | Proposed definition | B2 |
| N | Number of components | Standard variable | -- |
| q | Per-component match probability | Toy model parameter | This page |
Key Literature Referenced
| Reference | Result | Relevance to C1 | |---|---|---| | May (1972) | Random interaction models: larger, more connected systems with stronger interactions become less stable | V alone (more complexity) does not guarantee stability; architecture matters | | Benzi, Sutera & Vulpiani (1981) | Stochastic resonance: noise can enhance signal detection in specific nonlinear systems | Non-monotonic V-performance relationship; V* concept | | Gammaitoni et al. (1998); Moss et al. (2004); McDonnell & Ward (2011) | Reviews of stochastic resonance theory and experiments | Specific conditions required: nonlinearity, subthreshold signal, appropriate noise range | | Kuramoto (1975, 1984) | Synchronization phase transition in coupled oscillators | Coordination (kappa) emerges from variation through coupling | | Kauffman (1993); Langton (1990) | Edge of chaos / critical regime in Boolean networks | Intermediate variation regimes are often optimal | | Bak, Tang & Wiesenfeld (1987) | Self-organized criticality | Systems may self-tune to critical V-kappa regimes |