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Logic Principles of the Tripartite Synapse Model
These are the principles that govern the model's logic — not the syntax in which it is expressed, but the reasoning that shapes every variable, every behavior, every transition.
A note on language. This document does not say "the system." There is no system — only local components, each reading arrived signals and acting on its own state. "System," "whole," "network," "the organism's memory" are names applied from outside, by us, describing what coupled local components do together. The first principle states this; the rest honor it by never speaking in the voice of a whole that does not exist. Where a sentence seems to want "the system does X," it is rewritten as "local components, contextualized thus, do X locally" — because the form of the document should enact its central claim, that locality goes all the way down and all the way up, with no privileged vantage anywhere inside.
The ten categories run foundation-first. The closing category — the Three-Phase Ring — is the integrator: it shows how a single cycle of ACTION → EVALUATION → PREPARATION, run locally by every component and turned in two directions (outward by DAY, inward by NIGHT), is where all the flows the earlier categories describe actually happen in time. It comes last because it uses everything established before it. A vocabulary note on motion: causation circulates across scales (category VI); the ring turns across phases (category IX). Two different loops, two different words, kept distinct.
I. There Is No System; Holism Is Real but Only Described
There is no system — only local components. Nowhere in the model is there a controller, a global plan, a representation of the whole, or a vantage from which the whole is seen. There are only components, each reading the signals that physically reached it and acting on its own state. Every behavior is local; every evaluation uses only local state and arrived signals; every trace is a local record; every commitment a local draw on a shared pool. "System" is our word for the aggregate, spoken from outside. No component is the system, occupies its standpoint, or can read it — not the smallest bouton and not the highest integrating actor.
And yet what we describe as holism is real. Memory, rhythm, selection, consolidation, sparsification — these are real behaviors, not illusions. The puzzle is that they are real without any whole existing to bear them. The resolution: they are enacted by coupled locals, never encoded in any one of them or in any representation. The holism is in the doing — the ongoing competitive, signal-mediated, scope-alternating process of many local components — not in any part and not in any model the parts contain.
What couples the locals is what we then describe as a whole. Three couplings do all the work. Shared pools: the only thing every component touches is the finite resource it competes for; when one draws, the others have less, when one returns, the others have more — local actions become mutually consequential through a common, capped resource. Cross-scale coincidence: a lasting change requires confirmations from larger scales that no component can produce for itself, so every lasting change records an agreement across scales that no single scale authored. Signals: components cannot read each other, but they emit and receive, so they are coupled without any one gaining access to another's interior. Through these three, purely local action acquires what we describe — from outside — as global organization.
The properties we call holistic belong to no component. Rhythm, equilibrium, memory, the joint selection for significance-and-sustainability — none exists in any single component. They are descriptions of the coupled population over the DAY/NIGHT alternation. The gap between "what a component knows" (only its own state) and "what we describe the population as doing" (choosing what to keep) is not bridged by any component knowing more. It is bridged by the coupling itself. Understanding, here, is enacted, not encoded — and "the system understanding" is only ever our shorthand for coupled locals enacting, faithfully local at every step, holistic only in our description.
Even the cycle is local. Each component runs its own three-phase ring (category IX), its phase boundaries set by its own trace decays, not by any shared clock. There is no global cycle any more than a global controller — only many local rings, loosely coupled through shared pools and signals, which we describe together as "the rhythm." The turning is real in each component; the collective rhythm is our description of many local turnings.
II. Two Contextualizations, and the Loop Between Them
DAY and NIGHT are not two phases of a system; they are two contextualizations of the same local components. A component does one kind of thing always: it reads arrived signals and acts on local state. What changes between DAY and NIGHT is the context that fixes what those signals mean, who the component's counterparties are, and what is scarce. By "DAY" we name the contextualization in which the relevant environment is the external world and the component's information is about exogenous events. By "NIGHT" we name the contextualization in which the relevant environment is the internal economy and the information is about endogenous resource-state. The component cannot tell which it is in — it has no access to "the scope" any more than to "the system." It reads local signals, and context makes them mean what they mean.
Each contextualization has its own environment and its own information. NIGHT is not the absence of an environment — it is interaction redirected from the world to the self. By day a component interfaces outward, perceiving sensory-driven events and reward; by night it interfaces inward, perceiving how much resource reached it, what its peers are claiming, what coheres. Both are full perceive-act loops against a real environment. Resource levels and demand-signals are the night's perceptual field exactly as glutamate and dopamine are the day's. "Internal" and "external" are relative to the subject one fixes; from a component's own standpoint there is only "my environment" — the signals reaching me — which happens to be the world by day and the economy by night.
A component is thus two contextualizations sharing one structure. By day it is an environmental interface; by night an economic agent. The two share only the structure, and the structure is exactly what carries between them: the night-agent builds the ceiling the day- interface will operate within, and the day-interface generates the evidence (the tag) that authorizes the night-agent to build. The tag is information becoming a resource-claim at the boundary — the single unit that crosses from the day's information-context to the night's resource-context.
The move between the two is an emergent local transition, not an imposed clock. There is no global day/night switch. Each component enters its NIGHT when its own activity is low and an arrived sleep-pressure signal is high, and returns to its DAY when that signal falls. Both conditions are read locally — own activity, arrived signal — so the transition is itself a local decision. Components therefore cross over at different times: a wave, not a switch (local sleep). The signal that carries them is itself the product of locals: activity generates fatigue; fatigue, integrated by one component (the hypothalamic actor) that does nothing but integrate fatigue and emit pressure, raises sleep-pressure; high pressure plus a component's own quiet opens its restructuring window; restructuring discharges fatigue; discharge lowers pressure; the component re-enters DAY. DAY and NIGHT are the two phases of one homeostatic loop the local components run on themselves — neither imposed from outside nor scheduled from above. The component never knows it is "in NIGHT"; it reads a signal level and its own activity, and what results we call night.
The mechanistic root of the alternation: behavior and restructuring exclude each other. A component cannot rebuild its structure while it is busy behaving — the two compete for the same substrate. Only when its activity is low does it have the access to its own architecture that restructuring requires. The brief low-activity gaps within a day permit small adjustments; the sustained, widespread quiet that the sleep-pressure signal creates permits the large ones. NIGHT is not an arbitrary time for consolidation — it is the condition under which consolidation is possible, because quiet is what grants a component access to itself.
Two distinct couplings join the scopes — do not conflate them. The scopes are connected in two independent ways. The fatigue loop is the switch: it controls when a component crosses between DAY and NIGHT (activity → fatigue → sleep-pressure → transition), a purely temporal control carrying no content. The evaluation handoff is the payload: it passes what each scope leaves for the other (the tag minted by day's evaluation, consolidated by night; the structure minted by night's evaluation, read by the next day — see category IX). One says when to switch; the other says what crosses. A reader who merges them loses the fact that a component could switch scopes with nothing to hand off (a quiet day leaves no tag) or hold a rich payload that waits several switches to be honored (a tag consolidated over several nights). Switch and payload are orthogonal.
III. Locality and Signals
Only local evaluation. Every decision a component makes — to act, to deposit a trace, to register an interrupted success — uses only information physically present in it. It cannot read another component's interior. The presynapse does not know the postsynapse's calcium; the dendrite does not know which distal spines are active; the astrosynapse does not know whether the postsynapse is waiting. Each judges from its own state alone.
A component cannot read the whole, either. The completion of locality: not only can no component read another's interior, none can read "the system," "the scope," or the global state. There is no aggregate vantage available anywhere inside — not even to the integrating actors, who read only the summed emissions that reached them and emit signals in turn, with no more access to the whole than a bouton has. Locality holds up the hierarchy as strictly as across it.
Cross-component influence travels only as signals that arrive and become local. Information crosses a boundary only by being emitted — feedforward transmission, retrograde messengers, neuromodulatory and sleep-pressure broadcast, the demand and recycled resource of the night economy. A signal in transit is invisible; a signal that has arrived is local and can be read. Downstream reaches upstream by emitting; upstream never reaches into downstream. Every coupling in the model is of this form — an emission that becomes, on arrival, another component's local state.
Everything emits; nothing is a pure sink. No component only consumes. Each, whatever it receives, emits something a neighbor will read — its transmitter, its retrograde feedback, its fatigue, its demand, its recycled material, or simply its activity for an integrating actor to sum. The direction of emission reverses with context (see the two Logic panels): outward and downstream by day, inward and upstream by night. But the invariant holds in both — there are no leaves and no sinks, only a reversal of which way "out" points.
IV. Resource and Conservation
Nothing is free. Every behavior consumes a resource. There is no operation that does not draw something down. This is not a constraint added on top of the logic — it is its foundation. Selectivity, competition, and forgetting all follow from the single fact that resources are finite.
Resources are redistributed, not created. The pools are bounded by external ceilings. Within them, resource is only moved — from one site to another, from a dismantled structure back to the pool. No internal process manufactures capacity; it only reallocates. A gain anywhere is paid for by a loss elsewhere — coupling that is not designed but is the automatic consequence of drawing from a common pool.
Two resources, two conservation laws. Energy is a flow — produced and consumed, gone after use. Material is a stock — incorporated into structure and recovered when structure is dismantled. Different sources, different recovery. A behavior can be energetically affordable yet materially limited, or the reverse. Keeping them distinct is what makes the accounting honest.
Material circulates; energy ratchets — energy is the one irreversible flow. This is the sharp form of the distinction, and it is the arrow of time. Material cycles indefinitely: spent into a ceiling, recovered when that ceiling decays, returned to be spent again. Energy does not. It is produced fresh at the roots, burned irreversibly on the work of building and behaving, never recovered. Everything else cycles or relaxes — traces decay and reform, occupancy fills and drains, material recycles — but energy only ever goes down per unit produced, capped externally by glucose. The total learning the local components can ever do is bounded by their lifetime energy throughput, and no internal cleverness lifts that bound. The irreversibility of energy is what makes them age.
Every economy has a single capped root. Each resource traces to one producer with a hard ceiling — the astrocyte cell body for synaptic energy, the soma for neuronal material. Everything downstream competes for shares of that capped production. The ceiling is set from outside and is the ultimate arbiter of how much can be done.
Scarcity is what forces choice, and choosing is learning. What is consolidated is the outcome of bounded demand (the standing tags and endurance needs) meeting bounded supply (the energy and material produced each night), and the match need not clear — a night may run out of energy before it runs out of demand. Unmet demand is not discarded but carried forward and retried. The selective pressure is, at bottom, this repeated failure of supply to fully meet demand: it is because not everything can be afforded that there must be choosing, and the choosing is the learning.
V. The Timescale Ladder
The spine. Every quantity sits on one of four nested tiers, and timescale is not incidental to it — timescale is its meaning.
Four tiers. FAST traces (ms–s): residual calcium, synaptic current — the immediate response. MEDIUM occupancy and evidence (s–min): the filled receptor surface and channel coupling, the accumulating possible-tag, the endurance need. The SLOW tag (hours): the validated bridge to consolidation. PERSISTENT capacity (written only at night, drifting over days): the structure and budget ceilings. A quantity's decay constant is what it means — a fast-decaying quantity is a momentary signal, a slow one a commitment, a non-decaying one a capacity. Putting two timescales in one variable destroys both meanings, which is why a quantity carrying both a momentary and a lasting role is split into two.
Capacity and occupancy are two rungs, not a separate principle. What was once stated as "night builds containers, day fills them" is simply this: the PERSISTENT tier is written at night and bounds the MEDIUM tier, which fills by day within it. The same physical quantity — receptor count, vesicle coupling, fuel level — has a fast/medium component (how full, occupancy) and a persistent component (how big, capacity), governed by different processes at different tiers. Short-term change is occupancy; long-term change is capacity; they never do each other's job.
Two capacities, two drives, one pool. Structure is the capacity for strength — how powerfully a behavior can act. Budget capacity is the capacity for endurance — how long it can be sustained. Both are persistent ceilings, both filled competitively at the medium tier, both drawn from the same finite material and energy, so strength and endurance compete. A ceiling of either kind is never free even by day: filling it costs a competitive share of a shared pool, and a high ceiling makes a large standing claim satisfiable only by out-competing neighbors. Capacity that cannot be filled is wasted.
Structure shapes form, not just maximum. A ceiling does not merely cap — it conditions the transfer function at every moment. Tighter calcium-channel coupling makes each spike more reliably coupled to release; more anchoring slots convert each pulse more faithfully to current; tonic co-agonist keeps the gate primed. The persistent tier shapes the quality of behavior continuously, not only its peak.
The tiers are a ladder: each rung's output is the next rung's input, in both directions. Evidence ascends — fast traces accumulate into medium evidence, which bridges (on validated coincidence) into the slow tag, which commits at night into persistent capacity; nothing reaches a slower tier without accumulating through the faster ones. Capacity descends — persistent structure bounds medium occupancy, which bounds fast behavior; the ceiling at each level was set by the level above, on a slower timescale. Both the strength pathway (trace → possible-tag → tag → structure) and the endurance pathway (trace → endurance-need → budget ceiling) are the same upward climb, differing only in what validates it: associative dopamine for strength, homeostatic fuel-shortfall for endurance.
A pool's recovery timescale is what its exhaustion means. The ladder governs pools as well as traces. A fast pool (the readily-releasable vesicle pool) depletes and recovers fast, so its shortfall is transient — short-term depression, self-correcting once activity slows. A medium pool (operational budget) recovers at the medium scale, so its shortfall is a standing constraint worth recording as endurance evidence. Persistent capacity changes only at night, so its "shortfall" is a structural limit unfixable in the day. This is why a behavior's failure mode can be read off which pool ran dry: fast-pool exhaustion is depression, medium-pool exhaustion is endurance evidence, persistent limit is structural. Depletion-and-recovery is the pool-side mirror of creation-and-decay — drawn down by behaving, refilled toward a ceiling — and in both, the timescale is the meaning.
The ladder is structure; the ring is timing; they are orthogonal and they compose. The ladder (this category) is about tiers of persistence — which quantities last how long, and how capacity descends while evidence ascends. The three-phase ring (category IX) is about phases of a cycle — when a component acts, evaluates, and prepares. These are independent axes: one could have the ladder without a cyclic ring (a pure feedforward hierarchy) or a ring without four tiers (a cycle at one timescale). They compose in a specific way: the ring's phases are where the ladder's flows occur. ACTION injects at the bottom of the ladder (deposits the fast trace). EVALUATION enacts the up-flow (works the fast trace into medium evidence and the slow tag). PREPARATION enacts the down-flow (reads the descended capacity as the readiness the next action runs within). So the two pictures are not two names for one thing — the ladder says what persists, the ring says when each persistence-flow happens, and evaluation-is-up / preparation-is-down is where they meet.
VI. Causation Circulates — Emergence Up, Constraint Down, Command Nowhere
The model has causation in two directions, and the whole point is that they coexist without either becoming control.
Emergence flows up. What we describe as global organization — sparsification, normalization, winner-take-more, the allocation of fuel — is nowhere computed centrally. It emerges from many local components drawing on shared pools. No allocator decides which synapses to fuel; the synapses' own demands, each purely local, competing for capped production, produce the allocation. No allocator exists; the allocation is real. The local emissions sum, through the pool, into an aggregate no component authored.
Constraint flows down. An integrating actor holds an aggregate its constituents cannot see — total weight, territory demand, accumulated fatigue — and broadcasts it back as a constraint each constituent then interprets locally. The neuron, summing emitted activity it never reads interiors to obtain, broadcasts a renormalization that each component applies to itself. This is top-down, but it is constraint, not command: the higher actor sets a bound; the lower still decides locally within it.
Command exists nowhere. This is the load-bearing claim. The downward direction never becomes a higher component deciding for a lower one, nor a lower one deciding for itself in isolation. No actor authorizes its own restructuring — each is put in the position to restructure by the actor above it, which holds the aggregate it cannot see and opens the quiet window it cannot open, then broadcasts, never reaching in. The soma cannot decide within the soma; it is put in position by the neuron — which is itself put in position by the integrated fatigue, which is itself the sum of what the components emitted. Causation circulates — up as emergence, down as constraint — and the circle closes with no controller anywhere on it. Every integrating actor is itself only another local component reading summed arrived signals; none is "the system" in disguise.
The recursive grant repeats at every scale. The relationship is the same all the way up: the astrosynapse is put in position by the astrocyte; the soma, bouton, spine, branch, axon by the neuron; the neuron and astrocyte by the hypothalamic fatigue signal; the synaptic strengthening by the organism's dopamine and the assembly's replay. Each scale grants its constituents the conditions they cannot grant themselves — an aggregate they cannot see, a window they cannot open — and grants it by signal, never by reaching in. The hierarchy is real, the circulation is closed, and at no point does it produce a seer of the whole or a commander of the parts.
This cross-scale circulation enters each component's ring at a definite phase. Causation circulates across scales (this category); a component's ring turns across phases (category IX) — two different loops. They meet at a definite point: the downward constraint arrives at the component's PREPARATION phase, whose subject is precisely "what is handed down from above," and the upward emergence departs as what the component emits during ACTION and commits during EVALUATION, which sums into the aggregate the scale above will read. So the vertical arm of the cross-scale circulation is lived, inside each component, as the vertical phase of its ring. The three subjects of the ring (beside / self / above) are the three ways a component connects to everything else, and each of the other categories' flows plugs into the phase whose subject matches it.
VII. Selection and Asymmetry
Building is the active drive; weakening is its shadow. All the machinery is oriented toward strengthening what is significant and sustaining what is fuel-limited. There is no symmetric machinery for weakening. Weakening happens to whatever the building machinery did not select, as a consequence of the resources building consumed. The orientation is toward learning; forgetting is its cost.
Depression is never explicit — it is what happens when building does not. No signal says "weaken this." Ceilings of both kinds decay continuously and are held up only by maintenance; when building consumes the shared resource, unmaintained ceilings drift down. Depression is the absence of maintenance, not the presence of a depression signal — and the same is true of lost endurance, idle capacity removed for lack of use, and of occupancy, which drifts back the moment its driving trace decays. In ring terms (category IX), this decay lives in the PREPARATION phase: weakening is what preparation's settling does to whatever evaluation did not supply enough to maintain. There is no weakening phase because weakening is un-honored decay inside the preparing phase.
Validation enters from beyond the part; the part cannot validate itself. A component cannot know whether its own activity was significant — that information exists only at a larger scale and arrives as a signal (the neuromodulatory broadcast for the organism's verdict, replay for the assembly's). Cheap reversible change is autonomous; expensive lasting change requires authorization that enters from outside the component being changed. This is why lasting change always records a coincidence across scales: each scale confirms what the one below cannot know about itself.
Strength is associative; endurance is homeostatic. Strength requires significance — the dopamine coincidence saying "this was worth saving." Endurance requires only that fuel, not structure or significance, was the binding constraint on a forming success — it needs no external validation, because metabolic sustainability is not the organism's to judge but the component's own to register. Two independent criteria, and selection requires winning on both: activity without significance is not saved; significance without sustainable fuel cannot be maintained. The conjunction filters for connections both valuable and viable.
Equilibrium is the residual of imperfection. Where alignment or balance is reached, the success removes the very signal that drove it, allowing slow drift back, which regenerates the signal. The soma that aligns to its input rhythm stops generating the mismatch that aligned it, drifts, and re-aligns. The component that builds enough endurance stops depleting, loses the signal, and lets capacity decay until depletion returns. Each component hovers near its own optimum, never resting there, corrected continuously by the small errors its own imperfect state produces. What we describe as a stable population is the sum of these local never-quite-settlings.
VIII. Coupling, Openness, and Boundedness
Couplings create trajectories, not just states. Some variables, once moved, make further movement the same way easier — the astrosynapse wrapping tighter after potentiation, easing future potentiation. These self-reinforcing couplings give momentum: components do not merely occupy states, they follow trajectories, deepening whatever direction they have begun. The astrosynapse is the strongest such coupling — the gain control that reshapes the input itself, amplifying whatever trajectory a synapse is on.
The same signal serves opposite functions through different receivers. Glutamate spillover brakes the presynapse while exciting the astrosynapse — one ligand, two receptor types, opposite cascades, simultaneous opposite effects. Function is set by the receiver, not the signal. One event coordinates several responses with no coordinating mechanism.
Metabolic availability is a selective pressure parallel to validation. Beyond the explicit activity-and-reward gating, the bare availability of fuel continuously selects which components can participate: one that cannot be fueled cannot generate the activity that would let it be tagged. Metabolism silently shapes what can be learned, independent of and parallel to the plasticity machinery.
Finite and open, not infinite and closed. The components are bounded and their state space is bounded, and they receive inputs they cannot generate from within — sensory drive, neuromodulatory and replay validation, metabolic supply. Because they are finite, their self-modification generates no infinite regress. Because they are open, their highest validation comes from outside any component being changed.
The fixed points are explicit, not hidden. The quantities the components cannot modify from within — thresholds, the vascular ceiling, the neuromodulatory and replay signals — are declared as given. They are the boundary with what the components did not set and cannot inspect. Making them explicit is the honest acknowledgment that every self-modifying process operates within constraints it did not choose. Correctness is never certified internally: whether a change was good is answered by the organism's later experience in the world, fed back as signal. The fixed point lies outside — the components act, the world responds, and the response, not any internal check, determines what was worth keeping.
IX. The Three-Phase Ring, and Its Two Turnings
This is the integrator. Everything above describes what flows — resource, evidence, constraint, signals, capacity. This category describes when: the single cycle each local component turns, and how the earlier categories' flows distribute across its phases. One ring, run locally by every component, turned in two directions — outward by DAY, inward by NIGHT.
The ring has three phases, given by the three relationships a component stands in. A component relates to exactly three things — its peers beside it, itself, and what is above it — and the ring is one turn through all three:
- ACTION (subject: peers, lateral). The defining interaction with the component's counterparties. It is punctate — an event — and it deposits a fast trace, the residue the rest of the turn will read.
- EVALUATION (subject: self, local, handing to the other scope). In the quiet after the action, the component reads the fast trace and works it up the ladder into slower evidence. It never acts; its product is an inert token minted for the other scope.
- PREPARATION (subject: what is above, vertical, readying the next action in this scope). As the trace decays, the component settles its pools and gates forward, reads what has descended, and assembles the readiness the next action will run on. Preparation is the sole gateway to action.
The order around the ring is ACTION → EVALUATION → PREPARATION → ACTION. Because it is a ring, no phase is first; each turn's preparation feeds the next turn's action, and each turn's evaluation reads the action that preceded it.
The ring is necessary; its co-location in one component is not. What the logic guarantees is that the ring closes — that every action is evaluated and every action is prepared for — not that any single component runs all three phases itself. A component necessarily has ACTION: the local act it performs is what makes it a component at all. But the EVALUATION and PREPARATION of that act may live in other components. Take the calcium channel as a component: its ACTION is letting Ca²⁺ in — that is its whole local act. It does not evaluate whether the influx mattered (the presynapse does, reading the resulting trace) nor prepare its own next opening (its coupling readiness is set by presynaptic short-term potentiation, and above that by neuronal provisioning). The channel is almost pure action; its evaluation and preparation sit in the components around and above it. Yet the ring is intact — the influx is acted, evaluated, and prepared for — merely spread across three components rather than turned within one. So the ring is a property of coupled components, not of the individual: a component contributes its action, its neighbors and superiors contribute the evaluation and preparation that action requires, and together they close a ring none of them runs alone. This is the same frame as category I — there is no ring-bearing "self," only local components whose coupled actions we describe as one closing ring.
Action is always local; evaluation and preparation may be local or contextual. This is the axis beneath the previous point. A phase is local when the acting component supplies it itself, contextual when a surrounding or higher component supplies it. Evaluation and preparation come in both forms: the presynapse evaluates its own release and prepares its own next release (local), while the calcium channel's influx is evaluated by the presynapse and prepared by neuronal provisioning (contextual). Action admits no such split — it is always local, and necessarily so. A component can hold an aggregate and evaluate a neighbor's trace on its behalf, or provision a neighbor's readiness; but it cannot act on a neighbor's behalf, because the action simply is the local event occurring in that component. To perform another's action would mean it was never that component's action to begin with. Acting-for-another is not action but signalling. So the one phase that can never be contextual is action, and this falls directly out of what action is — which is why every component necessarily has its own action, while its evaluation and preparation may be scattered into its context.
The phases are event-delimited and decay-timed, never clocked. A phase has no fixed duration. The action is the boundary where preparation ends and behaving begins; the fast trace's decay below threshold is roughly where evaluation ends and preparation resumes. The quiet interval between actions — a component's refractory-like period, whether literal refractoriness at the soma or the NOT-active steps at the bouton — is where evaluation and preparation live, and its length is set by the firing pattern. A fast train compresses preparation to nothing (no time to refill: depression); sparse action gives preparation its full extent. Timing here is chemistry, not a timer (category V).
Evaluation and preparation share the fast trace but send it two ways. The same trace the action deposits is read by both: evaluation reads it for significance (climbing toward the tag, for the other scope), preparation reads it for readiness (tuning the next action's timing and thresholds, in this scope). The soma makes this visible — its nuclear-calcium climbs toward the tag (evaluation), while its inactivation, adaptation, and alignment traces tune the next spike (preparation) — all from the one spike's deposit. Evaluation looks up and across scopes; preparation looks around the ring to the next action.
Evaluation reaches the next action only through preparation. Evaluation never acts; it lays down inert evidence. For that evidence to shape a future action it must pass through preparation, on one of two timescales. Within a scope: evaluation's medium products (possible-tag, endurance-need) become preparation's inputs, folded into near-term readiness. Across scopes: evaluation's slow product (the tag) waits, is consolidated into structure, and structure is read by the next scope's preparation. Either way — evaluation proposes, preparation disposes, action runs. The one-way ring is what separates gathering from acting by exactly the time it takes preparation (or the night) to honor what evaluation proposed; that separation is where deliberation lives.
The coincidences of the action sort by timescale. Where a component detects the coincidences that authorize a lasting change depends on whether they must be instantaneous. Coincidences that must be simultaneous are detected in ACTION by the receptors themselves — the postsynaptic NMDA gate passing large calcium only when presynaptic glutamate, astrocytic co-agonist, and local depolarization align, amplified by the descended back-propagating spike. Coincidences that can be integrated over the quiet are detected in EVALUATION by trace accumulation — the organism's dopamine gating the tag over the following interval. Same logic (require several partners to align), sorted into the phase whose timescale it fits: instantaneous coincidence is action, integrable coincidence is evaluation.
The two turnings
The subjects are invariant across DAY and NIGHT; only the content that flows through them transposes — information by day, resource by night. From the component's own standpoint there is no "open" or "closed" scope: each turning runs against its environment, which is the world by day and the economy by night.
DAY — the ring turned outward. ACTION is the cleft exchange (release, integrate, clear) against the external environment, leaving the fast trace. EVALUATION climbs the ladder to the tag — information worked up toward significance, minted for the night. PREPARATION reads the descended structure and refills the pools toward the next behavior. Currency: information, cheap and gathered passively. Direction on the ladder: evidence ascending. Handoff token minted: the tag.
NIGHT — the ring turned inward. ACTION is the coherence check: the component signals its standing claim into the same channels, now economic, and reads whether its peers concur — the lateral interaction, its content now "should this be kept" rather than "transmit." It leaves a coherence verdict, the night's fast trace. EVALUATION is draw-and-commit: reading the verdict, the component burns energy and material into structure only if coherence was found, spending its tag — minting the token for the next day. PREPARATION is make-room: receiving the constraint broadcast from above, recycling material from decayed ceilings, resetting for the next round's building. Currency: resource, scarce and fought over. Direction: capacity descending, demand ascending. Handoff token minted: the structure.
The two turnings are stitched together by evaluation. Each scope's EVALUATION mints the token the other scope's PREPARATION consumes: day-evaluation mints the tag, night consolidates it; night-evaluation mints the structure, the next day reads it. The tag is information becoming a resource-claim; the structure is resource becoming the bound on future information-gathering. The DAY/NIGHT alternation is therefore not two separate cycles but one ring turned in two directions, handing off to itself through evaluation — tag outbound to the night, structure outbound to the day. The fatigue loop (category II) switches which way the ring is turning; the evaluation handoff passes what crosses when it turns. Switch and payload, one ring, two turnings.
Why night must cycle its turnings. By day the ring turns once per action and the actions come whenever the world drives them. By night the turning repeats in rounds because coherence is reached by different components at different times: a component that finds no coherent peers in one round's ACTION draws nothing in its EVALUATION, holds its tag, returns its resource to the pool for peers that did cohere, and turns again — its PREPARATION making room for a retry. Deferral is free because evaluation only spends when coherence is found, and energy, the irreversible currency (category IV), is burned only at the moment of coherent commitment. So the night is many turnings of the one ring, converging as coherence spreads, ending when demand is discharged or the night's energy is spent — and a change that never coheres before its tag decays is simply never spent on, which is how the turning forgets.