Moore's law

The empirical observation that transistor count per economically optimal integrated circuit doubles roughly every two years — a self-fulfilling industry roadmap that coordinated investment across the semiconductor supply chain so the complementary inputs for each process node arrived together.


Moralistic fallacy

Detect the inference that runs from normative undesirability straight to empirical falsity — 'this would be bad if true, therefore it is not so' — foreclosing a factual question on a moral ground without any evidence being weighed, the mirror of the naturalistic fallacy.


Morphology

Analyze the unbounded set of a language's word-forms as the output of a finite morpheme inventory combined by productive rules under ordering, surface-variation, and blocking constraints, so novel words parse on first encounter.


Motion-Triggered Harm

The inclusive-design failure in which interface animation, autoplay, parallax, or screen flash exceeds a susceptible user's physiological tolerance — a presentation channel that doubles as a harm channel, delivering an involuntary stimulus the median-calibrated design never accounted for.


Motte-and-bailey fallacy

Maintain a strong controversial claim and a weak defensible one under the same label, advancing the strong claim when unchallenged but retreating to the weak one under fire and resuming the strong claim once the challenge passes — so the motte's successful defence is misread as vindicating the bailey.


Moving the goalposts

An argumentative pattern in which, on being shown evidence that meets a previously stipulated standard, one party revises the standard upward to block the conclusion rather than accept it — repeated so that no finite evidence can settle the question.


Muller's ratchet

Explain the irreversible fitness decline of a finite asexual population as the stepwise, drift-driven loss of its least-mutated genotype class, which without recombination can never be reconstituted.


Multi-Instrument Coordinated Campaign

A single directing actor deploys a portfolio of qualitatively distinct instruments against a resistant target, timed and calibrated to cross the seams of its siloed defences, so integrated pressure exceeds what any instrument or uncoordinated set could achieve.


Multiplier Effect

Read the total output change from a one-shot spending injection off a single number — the leakage rate — by recognizing the successive re-spending rounds as a convergent geometric series summing to 1/(1−c) times the injection.


Munchausen Syndrome

The clinical pattern (DSM-5 factitious disorder imposed on self) in which a person deliberately feigns, fabricates, or self-induces medical symptoms with no external material reward, in order to occupy the valued role of the sick person — with a by-proxy variant enacted on a dependent.


Murphy's Law

The reliability-engineering posture that any physically permitted failure mode will eventually occur, so design must substitute 'permitted' for 'likely' — flipping the burden of proof onto anyone who would leave a permitted mode undefended, and driving enumerate-and-defend discipline.


Musical Form

Grasp a long musical work as a plan of related sections — introduced, contrasted, varied, and returned — matched to a named template like sonata or rondo, so the whole reduces to a sectional outline and an expectation arc the listener tracks.


Musical Texture

Classify a musical passage by how many simultaneous melodic lines it contains, whether they are independent or doubled, and whether one dominates while the others provide coordinated support.


Mutual-aid mismatch

The failure mode in which external support to an overwhelmed jurisdiction matches the gap in category but does not couple at the integration interface — wrong fittings, wrong radio plan, missing credentials, or post-peak arrival — so nominal aid yields no incremental capability.


Myelination

The process by which glial cells wrap insulating myelin around axons, forcing action potentials to jump between nodes of Ranvier (saltatory conduction) — raising conduction velocity an order of magnitude and cutting metabolic cost per spike, so conduction speed becomes the common variable behind milestones and demyelinating disease.


Naive Realism

Explain intractable disagreement as the converging conviction that one perceives the world directly, that all rational observers would agree, and that dissenters must be biased — relocating the dispute from the facts to each party's invisible construction of them.


Name-Letter Effect

Measure implicit self-positivity by the small, aggregate-only elevation in how much people like their own name-letters on a task framed as purely aesthetic and not cued to the self — a proxy that vanishes the instant self-relevance is made salient.


Narrative Gap

Turn a deliberate, cued absence in a story — a withheld fact or unrendered scene the reader is meant to feel and close by inference — into an active device tuned on one knob: the gap's width and signposting.


Narrative Paradigm

Walter Fisher's theory that humans judge value-laden arguments by narrative rationality — narrative coherence (does the story hang together?) and fidelity (does it ring true against experience?) — rather than by formal-logical soundness.


Native-advertising confusion

Diagnose a media artifact by splitting its content from its channel signal, so the failure becomes a decoupling — editorial-coded layout asserting journalistic provenance over commercially-incentivized content — and credibility tracks the signal, not the disclosure label.


Natural Capital

Treat a functioning natural system as a standing asset stock whose condition governs the future stream of ecological benefits, making depletion of productive capacity distinct from consumption of its current yield.


Natural Experiment

A design that borrows the RCT's identification logic from a real-world process — a policy, boundary, or lottery — judged plausibly as-good-as-random, where the as-if-random assumption must be substantively defended rather than guaranteed by protocol.


Natural Rate of Unemployment

The unemployment rate consistent with stable inflation in the long run — the frictional-plus-structural floor set by labour-market frictions and institutions, below which demand stimulus buys only accelerating inflation, never durable jobs.


Naturalistic Fallacy

The metaethical error of identifying goodness with a natural property, exposed by the open-question argument — for any proposed good = N, 'but is N good?' stays a meaningful question, so goodness cannot be identical with any natural property it merely co-occurs with.


Navigation loop

Diagnose a workflow where a user cannot reach their goal by modeling the interface as a directed graph and asking one structural question — is any goal state reachable from the current state? — rather than blaming screen quality or user confusion.


Near-equivalence Mapping

Bridge two concepts in different controlled vocabularies with a declared correspondence that carries an explicit, typed loss-risk on the bridge itself, so consumers can route each substitution on whether their use falls in the safe zone.


Near-Miss Effect

The operant finding that an outcome falling just short of the target — though it pays exactly zero — sustains responding more than a clearly distant failure, because the internal reinforcement signal is weighted by counterfactual proximity to the goal rather than by actual payoff.


Negativity Bias

Weight a psychological impact function asymmetrically around zero so that negative stimuli, events, and information claim disproportionately more attention, memory, and motivational pull than equally intense positive ones, at a stable offset ratio commonly running several-to-one.


Networked Publics

danah boyd's framework for how publics are structurally transformed on networked digital platforms by four architectural affordances — persistence, visibility, spreadability, searchability — which compound into context collapse and the invisible-audience problem and flip sociability from private-by-default to public-by-default.


Neuroplasticity

The nervous system rewires itself in response to experience by strengthening or weakening synapses under fixed rules of change, with how much it can rewire gated by a developmental window that is wide in youth and narrower in the adult.


Neurotransmission

Locate a neuron's flexibility not in the all-or-none spike but in the transformation across the synaptic gap — a quantal, probabilistic, context-modulated transfer decomposable into an ordered chain of mechanism slots that drugs and disorders each perturb at one point.


News Peg

The journalistic device of attaching a broader standing story to a timely trigger event through an editorial bridge, so a topic of enduring interest acquires a defensible 'why now?' and a licence to run in the current cycle — the peg being permission to publish, not the story itself.


News Values

The institutionally embedded criteria journalists apply to decide which events, from the surplus of occurrences, cross into coverage — a weighted bundle whose contingent weighting an analyst reads off an outlet's output, and whose silent excluded side is a site of power.


Newsworthiness

Score an event's fitness for coverage as a single relational property — computed against a specific outlet's criteria-bundle, the day's competing rivals, and a decaying window — that systematically diverges from the event's objective importance.


Ninety-Ninety Rule

The first 90 percent of the code takes the first 90 percent of the time and the last 10 percent takes the other 90 percent — a deadpan warning that nominal-progress metrics measure only the estimable bulk-work population and never the non-parallelizable, heavy-tailed completion tail.


Nitrogen Cycle

Track nitrogen as a conserved element moving through the Earth system by six microbially catalysed form-changing reactions, gated at the energetically expensive fixation step that limits biological access.


No Silver Bullet

Brooks's thesis that no single innovation will yield an order-of-magnitude gain in software productivity within a decade, because past gains already mined the accidental complexity (tool-and-environment friction) and the binding constraint is now essential complexity — difficulty inherent in the problem that no tool can dissolve.


NOAEL (No Observed Adverse Effect Level)

Anchor a substance's acceptable human exposure at the highest tested dose showing no observed adverse effect, treating that dose as a fact about the study's design that brackets — but does not pin — the unknown biological threshold.


Immaterial Spatial Entity

A spatial particular — a hole, room, or border — that has a location, shape, and history yet is constituted of no matter, individuated instead by its relation to material bearers, and admitted (or not) as a first-class entity by whether eliminating it into bearer-talk loses a fact.


Nonverbal Communication

Analyze face-to-face interaction as a finite set of meaning-bearing channels beyond words — kinesics, proxemics, haptics, chronemics, oculesics, vocalics, appearance — reading affect off the harder-to-fake channels when they diverge from speech.


Norm

Extract a single non-negative magnitude from a vector obeying three axioms (positive definiteness, absolute homogeneity, triangle inequality), where the choice among L¹, L², and L^∞ is a consequential modeling decision read off the unit ball's geometry.


Normal Fault

A fracture in the crust where the hanging wall has dropped relative to the footwall along a plane dipping near 60°, whose hanging-wall-down dip-slip geometry is the diagnostic signature of horizontal extension in the crust.


Not-Invented-Here Syndrome

Diagnose a team's systematic rejection of superior external solutions as a producer-attribution bias — quality judgments tracking source-of-origin rather than the artifact's properties — betrayed by asymmetric search depth and evidence weighting.


Novelty Effect

Recognise that a newly introduced stimulus draws an elevated response tied to its recency, not its intrinsic worth, which decays near-exponentially toward a steady-state baseline — so short-window evaluation systematically over-estimates the intervention's lasting effect.


Null dereference

The failure where code operates on a reference under the unstated assumption that the object exists, while the reference is in fact absent — so the defect is the missing existence-precondition check, not the absence itself.


Null Ritual

The institutionalised practice of mechanically executing a null hypothesis significance test — nil-null, p-value, p < .05 verdict — severed from the alternatives, priors, effect sizes, and decision context inference requires, yet retaining full editorial authority as if it had not been.


Nut Graf

Insert a paragraph early in a feature that lifts from the concrete opening to the larger pattern the story is about, transferring the reader's investment in the particular case onto the abstract significance so structural arguments survive abstraction fatigue.


Objective Correlative

Evoke a specific emotion in an audience not by stating it but by presenting a configured set of objects, situations, and events that is the formula of that state, so perceiving the particulars produces the feeling directly.


Ocean Acidification

The ocean's absorption of anthropogenic CO2 shifts seawater's carbonate equilibrium, lowering pH and — the load-bearing effect — the carbonate saturation state, so that below a saturation of 1 calcium carbonate shells dissolve rather than precipitate.


Ocean Current

A large-scale, persistent, directionally organized flow of seawater — set by a force balance among wind, pressure gradient, Coriolis, and friction — that advects heat, nutrients, and matter along a known path, wiring distant ocean basins into one coupled system.


Ocean Gyre

A basin-scale, quasi-closed rotating surface circulation set up by wind stress, the Coriolis effect, and continental boundaries, with a fast narrow western boundary current, a broad slow interior, and a convergent downwelling center that traps buoyant material.


Off the Record

Treat a source's condition as a post-transmission use-license: the information is transmitted and the journalist's orientation affected, but a defined class of downstream speech acts — publication, attribution, citation as evidence — is barred until the source upgrades or an independent source confirms.


Okrent's Law

The pursuit of journalistic balance can create imbalance, because equal procedural treatment of unequal evidence presses belief toward the weaker side by a margin that grows with the evidence gap — a thumb on the scale, not its absence.


Oligopoly

A market structure of a few sellers each large enough that its choices visibly move the others, so optimal strategy turns on anticipating rivals' responses — with the outcome swinging between competitive and monopoly-leaning by which equilibrium template (Cournot, Bertrand, Stackelberg, or repeated-game collusion) the market fits.


Omitted Variable Bias

Correct for the distortion in a regression coefficient when a left-out variable both causes the outcome and correlates with an included regressor, so the estimate absorbs the omitted effect as the signable product of two relationships.


On Background

The middle attribution tier where a claim may be published but the source is named only by a generic class descriptor — separating evidentiary content from source identity, with descriptor granularity a tunable knob trading warrant against identifiability.


Onboarding cliff

Diagnose first-use abandonment as a geometry of two curves — cumulative cost crossing the user's willingness-to-invest before cumulative value crosses willingness-to-stay — separating first-contact complexity from steady-state complexity and naming exactly two levers.


Ontological Paradox

Assess a self-causing closed causal loop — an object or piece of information that exists with no origin traceable outside the loop — by testing whether it is self-consistent (coherent, unlike the grandfather paradox) yet still lacking a traceable origin.


Open Availability

Make a knowledge resource reachable by anyone under explicit, non-restrictive, machine-operative terms so that reuse shifts from negotiate-per-use to consult-the-license, unlocking combinatorial composition across an ecosystem.


Open Innovation

The strategic stance in which a firm treats its boundary as a deliberately porous, governed variable for two-way knowledge flow — importing external IP and ideas inbound and releasing uncommercialized ones outbound — gated by absorptive capacity and stranded option value.


Open Set

A subset in which every point has neighborhood room entirely inside it — and, via three axioms on the whole collection τ, the primitive that IS a space's topology, letting continuity, compactness, and connectedness be defined with no distance function.


Operable Design

The commitment that every action an artefact requires must have at least one operationally-equivalent alternative path across input modalities and motor envelopes, so users are not gated out by assumptions about how actions are performed.


Operational Art

Name the middle command level between strategy and tactics as a distinct object of design, so a campaign's architecture — sequencing, decisive points, lines of operation, culmination — can be reasoned about as a whole rather than as a list of fights.


Operational Design

Insert a structured pre-planning phase that characterises the environment, frames the problem, and develops a revisable operational approach before any detailed plan, so a force does not solve the wrong problem with high precision.


Operational Pause

Deliberately halt active operations while still able to continue — trading present momentum for restored sustainment and a replan — timed to fall before the culminating point, past which recovery becomes impossible.


Operational-Pause Mismanagement

Diagnose when a pause taken to restore capacity instead hands initiative to a still-moving adversary, by budgeting it against the adversary's expected gain — a sign test on restart cost, exploitation rate, and ceded-window value — rather than against one's own expected recovery.


Operator-Vigilance Dependency

Name the safety configuration in which a human operator's unaided sustained attention is the final live barrier against a severe hazard, under exactly the monotony and rarity that the vigilance literature says will degrade that attention — worsened, not helped, by more upstream automation.


Opinion Leader

An intermediate node in a diffusion network who receives information from primary sources, reinterprets it through expertise and standing, and retransmits it as endorsed recommendation — carrying an audience-conferred interpretive authority no formal title supplies.


Order-Batching Distortion

The supply-chain failure in which a lumpy ordering rule converts smooth downstream consumption into artificial order spikes and troughs, which each upstream tier misreads as real demand and amplifies — one of the four canonical causes of the bullwhip effect.


Organizational Influence Failure

The accident-causation configuration in which upper-level resource, culture, and process decisions systematically stage the downstream conditions under which frontline operators produce unsafe acts — the apex of the HFACS four-level hierarchy, reclassifying the visible failure as the expression of an upstream choice rather than its cause.


Orientation Loss

Diagnose why a competent user gets lost by checking three location facts — where am I, what can I move to, how did I arrive — at each transition seam, reading the orientation state off the count of missing facts regardless of substrate.


Original Reporting

The journalistic practice of generating new primary evidence — by interview, on-site observation, document acquisition, or original analysis — rather than re-processing the public record, forming the irreducible base layer that caps the reliability of all derivative work above it.


Orogenic Belt

Read a mountain range, its foreland basin, and its metamorphosed core as one datable record of a single sustained plate convergence — reconstruct the collision's direction, style, and timing from the belt's hinterland-to-foreland polarity and brittle-to-ductile depth gradient.


Ostinato

Pin one voice to an unchanging short figure so the others are freed to develop against it — a layered-temporal asymmetry where the recurring layer anchors expectation and constrains the harmonic field, making variation above it legible.


Ostrich Effect

The pattern in which an agent actively avoids acquiring freely available, decision-relevant information whose expected content is bad news, because the anticipated affective cost of knowing outweighs the benefit of acting — so information acquisition becomes valence-sensitive rather than monotone in decision value.


Ostwald Ripening

Larger particles grow at the expense of smaller ones because higher surface curvature makes small particles more soluble (the Gibbs-Thomson effect), so material dissolves off them, diffuses through the matrix, and redeposits onto large ones — coarsening the population on a t^(1/3) law.


Outbreak Underascertainment

The surveillance failure in which recorded case counts fall systematically below the true count because a multi-stage detection pipeline — symptom expression, care-seeking, testing, confirmation, reporting — filters cases with biased attenuation at each layer.


Overburden Waste (Muri)

The lean-operations failure mode where people, machines, or processes are held continuously above their sustainable (not peak) capacity, converting apparent utilization gains into lagged, hidden costs — wear, defects, attrition, and downstream cascades — by consuming the very buffer that absorbs variation.


Overcoding

The qualitative-research failure mode where coding fragments material below the phenomenon's legibility grain, actively severing the sequence and relational structure that gave coded phrases their meaning — diagnosed by whether meaning can be reconstructed from the codes alone.


Overjustification Effect

The pattern where a salient external reward for an already-intrinsically-motivated activity makes the agent reattribute their motive to the reward, so that when the reward stops, activity falls below its pre-reward baseline — a crowding-out, not an augmenting, of motivation.


Overprocessing Waste

Name the waste of effort, precision, or handling that exceeds what the downstream receiver will use or pay for — relocating the definition of value from the performer to the receiver and making the effort-value gap a measurable target for removal.


P versus NP Problem

Ask whether every problem whose solutions can be verified in polynomial time can also be solved in polynomial time — turning the apparent gap between checking and finding into the open question of whether it is a structural barrier (P ≠ NP) or mere ignorance (P = NP).


PACELC Theorem

Classify a replicated data system by two regime-dependent trade-offs — availability vs. consistency under Partition, and Else (normal operation) latency vs. consistency — into a four-letter posture from which its workload behaviour reads directly.


Package-Deal Fallacy

Treat a set of positions bundled together only by coalition, tradition, or product line as if they were logically inseparable, so that endorsing one forces endorsing all and rejecting one requires rejecting the whole.


Papageno Effect

The documented pattern in which media narratives showing people surviving suicidal crises are followed by measurable reductions in population suicide rates, because an at-risk, identifying audience updates the salience of survival routes in their own option set.


Parachute Journalism

Diagnose systematically mis-framed foreign or crisis coverage as the equilibrium output of one conjunction — a non-local reporter, a sub-threshold access window, and a binding deadline — read off the single hidden variable, dwell time.


Paradox of Plenty (Resource Curse)

The resource-curse regularity that extractive-rent dependence can turn abundance into slower development through five reinforcing channels — Dutch disease, revenue volatility, severed tax accountability, conflict finance, and diversification crowd-out — whose mix and timing are gated by prior institutional quality.


Paradox of Thrift

The macroeconomic result that a simultaneous, economy-wide rise in the desire to save lowers total saving in equilibrium, because the coordinated withdrawal of spending contracts demand and income until realized saving falls.


Paradox of Voting (Downs Paradox)

Locate the puzzle that turnout far exceeds what instrumental rationality predicts by pinning the decisiveness term near zero in the pB − C calculus, so the entire observed turnout must be carried by non-instrumental terms outside it.


Parasocial Interaction

The one-sided felt relationship an audience member develops with a mediated figure — experiencing companionship, loyalty, or grief — while the figure holds no model of them, a constitutive asymmetry manufactured by the medium's performance conventions.


Paratext

Treat everything wrapping a text but not part of it — title, cover, preface, blurb, interviews — as a threshold that pre-sorts the work into a reception category and primes a reading strategy before the first page is read.


Parkinson's Law of Triviality (Bikeshedding)

Explain why a deliberating group allocates time to agenda items in inverse proportion to their consequence — because members contribute only where they can comprehend, so trivial-but-familiar items draw everyone while consequential-but-technical ones defer to a few.


Partial Agonist

A ligand that binds and activates a receptor but with intrinsic efficacy between zero and one, so even at full occupancy it produces a submaximal response — acting as an agonist when alone and a functional antagonist when a full agonist is present.


Partial Equilibrium

The Marshallian method of isolating one market and solving its equilibrium price and quantity off supply and demand while holding the rest of the economy as fixed background — trading economy-wide feedbacks for tractability, valid only when the studied market is small and weakly connected.


Participant Observation

Learn what only insiders know by holding a deliberate hybrid stance — participating in a social setting as a member would while keeping enough analytic distance to still notice what members take for granted.


Participatory Culture

Jenkins's mode of cultural production in which the audience is also producer, remixer, and mentor — the producer/consumer distinction collapsing at the role level — sustained by four tunable levers: low barriers, sharing infrastructure, mentorship pathways, and recognition economies.


Passivation

The phenomenon in which a reactive metal spontaneously grows a thin, dense oxide film from its own oxidation that throttles further corrosion by orders of magnitude — a self-limiting barrier that protects an underlying metal which remains thermodynamically unstable.


Peak-end rule

Predict the remembered value of an extended experience from just two moments — its most intense point and its final moment, averaged — while the duration and the integral of momentary affect over the interior receive near-zero weight.


Pedal Point

Sustain one voice on a single pitch while the surrounding voices move through the harmonic progression, generating licensed dissonance against the held tone that resolves when a consonating chord finally arrives — an arch of tension whose held degree fixes whether it builds or confirms.


Pedestrian Shed

Measure the true reach of a transit stop or destination by counting who can walk to it within a time tolerance along the actual street network, not the straight-line circle.


Peer Debriefing

Guard qualitative analysis against the researcher's own normalised assumptions by having a competent-but-removed outsider probe the reasoning while it is still revisable — producing not a verdict but a documented audit trail of what was challenged and what changed.


Perceivable Design

Require that every essential signal an interface conveys be decoupled from any single sensory channel and offered through an alternative at sufficient fidelity, so a user shut out of one channel — vision, hearing — is not excluded.


Perceptual Constancy

The phenomenon by which a perceiver holds an object's properties — size, shape, color, identity — stable despite large variation in the proximal stimulus, by inferring the distal property and implicitly factoring out the viewing condition.


Perceptual Set

Explain how prior expectation, context, motivation, or expertise biases what is perceived from ambiguous or degraded input — the percept is the prior weighted by how decisive the sensory evidence is, so the expectation dominates precisely when the stimulus underdetermines it.


Perfect Competition

The idealized market of many small price-takers trading a homogeneous good under free entry and full information, yielding price equal to marginal cost and a Pareto-efficient allocation — a benchmark whose five assumptions, when they break, name every standard market failure.


Perfect Order

Read fulfillment quality as one customer-facing scalar — the product of complete, on-time, undamaged, and correctly-documented sub-rates — so multiplicative decay (four links at 95% giving 81%) becomes visible and the binding sub-rate is read off directly.


Period Structure

Pair an antecedent phrase closing on a weak cadence with a consequent phrase closing on a strong one, so the cadential-weight asymmetry — a close that demands continuation answered by one that discharges it — binds two phrases into a single completed musical thought.


Peripheral Route Processing

The Elaboration Likelihood Model's low-elaboration pathway in which limited motivation or ability makes surface cues such as apparent expertise, attractiveness, message length, familiarity, and affect carry persuasion, producing attitude change that is cheap to acquire but comparatively labile.


Peso problem

Explain an apparent pricing anomaly — persistent forward-rate bias or too-good Sharpe ratios — as a sampling artifact, in which the price correctly embeds a rare severe tail event that the finite observation window happened to omit.


Phantom Inventory

Diagnose a fulfilment miss against a record showing healthy stock as an information-state failure — the record overstating reality between audits — that silently suppresses replenishment, pointing the fix at reconciliation cadence rather than the pick face.


Pharmacodynamic Antagonism

Diagnose why two co-administered drugs blunt each other by locating the opposition at the receptor or effector rather than at the concentration layer, then classify its binding geometry to read off whether more dose can overcome it.


Pharmacokinetic Interaction

Locate a drug-interaction failure at the exposure layer — one substance altering another's absorption, distribution, metabolism, or excretion so its concentration-time profile shifts at an unchanged dose — rather than as opposition at a shared receptor.


Pharmacological Interaction

Treat two co-present pharmacological agents as a coupled system when one changes the other's exposure or action, or their joint effect departs from the effect expected if each operated independently; then localize the coupling to the pharmacokinetic exposure layer or the pharmacodynamic effect layer.


Phillips Curve

The short-run inverse relation between unemployment and inflation — positioned by expected inflation, sloped by how anchored those expectations are, vertical at the natural rate in the long run, and displaced by supply shocks — whose exploitable trade-off dissolves once agents come to expect the inflation.


Phoneme

The smallest contrastively distinctive sound category in a language — the unit whose substitution at a position can change a word's meaning — defined not by its acoustics but by its place in that language's lattice of contrasts, and extracted by the minimal-pair test.


Phonological Awareness

Distinguish the trainable metalinguistic capacity to treat speech sounds as inspectable, moveable objects — to isolate, blend, delete, and substitute them — from the unconscious fluency every speaker already has, since in alphabetic scripts phoneme segmentation is the rate-limiting precursor of decoding.


Phonological Process

Read a child's scattered speech errors as the output of a small number of rule-governed transformations that apply productively across whole natural classes and drop on a predictable developmental schedule.


Phonology

Study speech sound as a closed language-specific system of contrasts — phonemes defined by what they are not, governed by phonotactic, allophonic, and prosodic rules — rather than as a catalogue of acoustic events, with the minimal-pair test extracting the inventory.


Phonotactics

Generate a binary well-formedness verdict for any phoneme string — including one never uttered — from a small constraint grammar of syllable positions, sonority sequencing, and adjacency rules, entirely before meaning is consulted.


Picture superiority effect

Pictures are remembered substantially better than the words naming the same referents because a picture is typically encoded in two independent codes — visual and verbal — whose retrieval routes OR-aggregate, while a word engages only the verbal route.


Pilot Purgatory

Relocate the diagnosis of an initiative that keeps running successful pilots without ever scaling from 'weak evidence' to 'a missing transition mechanism' — the loop is sustained by each pilot's local success, and the fault sits one level up in the decision infrastructure.


Pirate game

A toy sequential-bargaining model showing how backward induction in a propose-vote-or-eliminate mechanism lets the most senior proposer capture nearly the whole prize, because each voter's price is their continuation payoff and downstream subgames impoverish enough players to buy a cheap minimum coalition.


Pivot

Supply the missing middle option between persist and quit — a deliberate change of strategic direction that redeploys the calibrated learning from a disconfirmed bet — and locate it on a typed catalogue by asking which one dimension changes while the rest are preserved.


Pivot Thrashing

Diagnose a team that changes strategic direction faster than any one direction can close an evidence account — so it piles up change episodes without accumulating learning — by comparing its adaptation cadence against the evidence horizon.


Place Cell

A hippocampal neuron that fires only when the animal occupies a specific region of the world (its place field) — allocentrically referenced, so that the joint pattern across many such cells forms a distributed spatial code decodable to centimetre scale.


Place Field

Reify a place cell's spatial tuning as a measurable object — the bounded region where its firing rate is reliably elevated — turning 'the hippocampus represents space' into a battery of scalars (size, peak, stability, remapping) that travel across preparations.


Placebo Effect

An inert intervention produces a real, measurable improvement because the patient's expectations recruit the body's own regulatory pathways — which is why efficacy must be judged by a controlled comparison, not a single-arm gain.


Placemaking

The urban-design discipline that transforms a physical space into a recognised place — a location residents name, return to, and weave into routine — by treating place-quality as emergent from four mutually reinforcing loops (physical form, patterns of use, collective identity, and community stewardship) rather than as a property of design alone.


Plan-Execute Gap

The pathology in which a coarse-grained planning artefact cannot be enacted because the execution layer faces binding fine-grained constraints the planning model never represented — so the fix is constraint propagation and feedback, never a better forecast.


Planarity

The graph property of admitting a crossing-free drawing in the plane — pinned by Kuratowski/Wagner to a finite obstruction (no K₅ or K₃,₃) and by Euler's formula to a density bound, which is why a shelf of NP-hard problems turns polynomial on planar graphs.


Planetary Boundaries

Compress Earth-system risk into a nine-entry scorecard of biophysical control variables, each with a distance-to-boundary set conservatively below its nonlinear-transition threshold, defining a safe operating space for humanity.


Plate Tectonics

Explain Earth's large-scale surface structure through the relative motion of rigid lithospheric plates over a deformable mantle, with convergent, divergent, and transform boundaries coupling plate kinematics to subduction, rifting, earthquakes, volcanism, and orogeny.


Plot

Distinguish the causally bound, tension-shaped arrangement of selected events into a rising-climax-resolution arc from the mere chronicle of what happened in sequence — the move from 'and then' to 'because of' — and hold the underlying story fixed while varying its telling.


Documented Plurality of Users

Treat independent, publicly recorded adoption by multiple unrelated communities as graded evidence that a shared artifact codifies something general and fit-for-purpose — a warrant signal, not a truth-maker, that collapses the moment the adopters share a hidden source.


Poe's Law

Without an explicit marker of intent, a faithful parody of an extreme position becomes indistinguishable from a sincere expression of it, because sincere and parodic content overlap completely once the channel strips tone, context, and the sender's known standing.


Pointer

A small, fixed-size value that stores the memory address of another object, providing indirect access through three operations — take-address, dereference, and reassign — so linked structures can span non-contiguous storage and mutate in place by rewiring rather than copying.


Poisoning the Well

Pre-emptively discrediting the source of a forthcoming argument, so an anchoring frame of suspicion is installed first and every later thing the source says is received through it — including any rebuttal, read as defensiveness.


Policy Design

The structured activity of crafting an authorised rule for a target population of intentional agents inside an institution, factored into six separable components — frame, goal, target, instrument, implementation, evaluation — so failure can be localized to a slot rather than pronounced globally.


Polymerization

The process by which many small monomer units are covalently linked into long chains whose bulk properties emerge from the chain-length distribution rather than from any single monomer's chemistry — the chain, not the monomer, being the unit of analysis.


Polypharmacy

Shift the unit of clinical attention from the single prescription to the whole regimen, sorting the combined risk of concurrent drugs into three channels — pharmacokinetic collisions, pharmacodynamic summation, and the prescribing cascade — under one appropriate-versus-problematic binary.


Positionality

Treat a knowledge claim as constitutively shaped by the knower's social and institutional location, and declare that standpoint up front so readers can grant partial credit — strong where access opened, silent where it was foreclosed.


Positivity Effect

The age-graded shift in attention and memory toward positive and away from negative information, driven not by chronological age but by a narrowing perceived time horizon that re-weights goals — a goal-driven, load-sensitive strategy, not a passive decline.


Possibility Effect

People systematically overweight very small probabilities in risky choice, because crossing from impossible to barely-possible is a categorical shift in how an outcome is represented — the steep small-p branch of prospect theory's inverse-S weighting function.


Postel's Law (Robustness Principle)

Postel's protocol-design maxim — be conservative in what you send, liberal in what you accept — which keeps a multi-vendor system interoperable by having every implementation produce tightly to spec while its acceptance window absorbs the realistic scatter of others.


Potency

Quantify how much drug a given effect costs by reading one coordinate off the dose-response curve: the dose that produces half the maximal response (the ED50), so a lower value means less drug suffices.


Poverty Trap

A self-reinforcing development dynamic in which those below a critical resource threshold cannot accumulate enough to escape a low-level equilibrium — a bistable attractor where sub-threshold inputs are absorbed and reverted, while a large sustained push flips the basin and persists on its own.


Pratfall Effect

A small, recoverable blunder raises observers' liking for an agent already judged highly competent — humanizing them by narrowing a status gap — while the same blunder lowers liking for a mediocre agent, so the impression update reverses sign depending on the prior competence estimate.


Precedence Effect

When two copies of a sound arrive within a short critical window (~1–40 ms), the auditory system localizes the fused percept entirely by the first-arriving wavefront and discounts the lagging copy's spatial claim, while still letting it contribute to loudness and timbre.


Precipitation

Separate a dissolved substance as a solid once its concentration is driven past the solvent's solubility limit and a nucleation pathway opens, turning a latent supersaturation into an abrupt, self-limiting phase change.


Precondition for Unsafe Act

Name the immediate situational, personal, and team conditions — fatigue, distraction, a steep authority gradient — that raise the probability of frontline operator error, a distinct HFACS layer between upstream supervision and the unsafe act itself.


Precoordinated Heading

Fuse topic, place, period, and form into one canonical subject string at indexing time so users retrieve by matching a whole browsable label, trading expressiveness and easy schema evolution for that browsability.


Predictive Remapping

Explain trans-saccadic visual stability by having visuospatial neurons shift their receptive fields to a stimulus's future post-saccadic retinal position before the eyes move — driven by an efference copy of the saccade command, so the eyes land on an already-built representation.


Preferred Term

The single authorized form a stewarding body designates as the canonical label for a concept in a controlled vocabulary — with every synonym, abbreviation, and variant retained as a non-preferred entry that routes to it, so new indexing must use one form and any variant a searcher enters reaches the same record.


Primacy Effect

Items at the beginning of a sequence are remembered and weighted disproportionately, through two converging mechanisms — extra rehearsal cycles in serial recall and interpretive frame-setting in impression formation — so that the same content in different orders yields different beliefs.


Primitive Obsession

The code smell of representing domain concepts that carry structural commitments — units, valid ranges, well-formedness, identity — as bare primitives like int or string, so the type system cannot enforce the distinctions and they survive only as validation duplicated at every callsite.


Privacy Paradox

Explain the stable gap between people's high stated concern for privacy and their routine sharing of personal data for trivial benefits as a decoupling of attitude from choice behavior, produced by present bias, decision fatigue, opacity, and friction asymmetry.


Probability Distribution

The complete specification of how probability mass or density is spread over a random variable's possible values — a measure that, once compressed to a named parametric family, encodes shape, moments, tails, and a generative claim about the process producing the data.


Probability Weighting Function

Transform objective or stated probabilities into subjective decision weights, typically overweighting small probabilities, underweighting middle and high probabilities, and treating the zero and certainty boundaries nonlinearly.


Problem-Solution Fit

The lean-startup gate that demands cheap, need-side evidence — a real, important problem for an identified user, and a solution preferred over their current workaround — before committing to build at scale, guarding against 'build it and they will come.'


Problem-Solving Fixation

A familiar representation of a problem, method, or object becomes the first and dominant retrieval path, suppressing alternatives that the solver could otherwise use and producing an avoidable failure that can be relieved by disrupting the representation rather than adding knowledge.


Explain a material's behavior by inserting a mandatory mediator — structure — between processing and properties, with one-way causal arrows so intervention enters only at the processing end and design reasons forward through the structure it reaches.


Producer Surplus

The gap between the price a seller receives and its reservation price (marginal cost), aggregated as the area between the market price line and the supply curve — the seller's side of a conserved welfare ledger that any market distortion redistributes or destroys.


Product-Market Fit

Diagnose whether a venture is ready to scale by reading pull rather than push — a reachable audience actively retaining, referring, and paying for a product that beats their current alternative, rather than the producer forcing adoption through spend.


Productive Efficiency

The condition of producing a chosen output at the lowest feasible input cost — operating on the production frontier — with any interior point measuring recoverable waste as its distance inside, held strictly apart from the allocative question of whether the right mix is produced.


Productivity Paradox

The observation that economy-wide investment in a new general-purpose technology fails to show up in aggregate productivity statistics for years or decades, because measured gains lag the complementary intangible investment — process redesign, skills, restructuring — the technology's payoff actually depends on.


Program Realization Strategy

Assign how a formal program is turned into running behavior — by ahead-of-time translation to an independent artifact, direct execution by an always-present engine, or an adaptive mixture — and thereby fix when semantic work and its costs are paid.


Progress Illusion

Mistake high activity — story points closed, artifacts shipped, papers published — for progress toward a goal, a proxy substitution in which an easy-to-count activity signal stands in for a rare, hard-to-measure outcome construct because the activity really is tracking something, just not the goal.


Progress Indicator

A UI element that externalises a running process's position — how far along, how much remains, whether it is still alive — to resolve the uncertainty that would otherwise drive a waiting user to abandon or repeatedly check in.


Progressive-Disclosure Failure

Diagnose an interface's usability breakdowns as a single mistuning between its staging schedule and the readiness of the users and tasks it actually meets, read off by whether too much is hidden or too much exposed.


Prolepsis

Raise an anticipated objection in your own voice and answer it before an opponent can — 'you might object that X; but in fact Y' — bundling framing control (the objection arrives in its most rebuttable form) with a credibility display (the audience infers you have already survived it).


Prolonged Engagement

Treat sustained continuous presence in a field as a distinct epistemic regime, not merely more data — time-depth lets informants habituate toward natural conduct, lets context accrue, and lets early impressions be disconfirmed — up to the going-native threshold where analytical distance collapses.


Prompt Injection

Untrusted content delivered to a language model through a data channel is interpreted as instructions rather than material to process, so an embedded directive executes at the model's privilege — the failure being the absence of any in-band boundary between instructions and data, not a lapse in alignment.


Propaganda Model

Explain patterned media bias structurally rather than by motive — five institutional filters (ownership, advertising, sourcing, flak, ideological premise) shape every story before publication, so the slant is a property of the constraints, not anyone's intent.


Property-Based Testing

State an invariant that must hold for all inputs of a class and let a framework generate many samples, check each, and shrink any failure to a minimal counter-example — replacing hand-picked examples with systematic search over an input space.


Prosody

The supra-segmental layer of speech — rhythm, stress, pitch, tempo, and pause — that encodes meaning by patterning over the words rather than in them, so a fixed lexical string can shift between statement, question, command, or sarcasm purely through its envelope.


Protection Standard

Declare the named threshold up to which a system is designed to withstand a hazard class — which simultaneously frames every event above it as accepted residual risk, converting implicit unprotection into governed unprotection that can be audited, insured, and contested.


Psychophysical Scaling

Relate controlled changes in measurable physical stimulation to changes in sensation or discrimination by fitting a modality-specific response law over an explicitly bounded operating range.


Public Choice

The research program applying economics' rational-self-interest assumptions to politics — modelling voters, politicians, and bureaucrats as utility-maximizers responding to institutional incentives, so government failures read as predicted equilibrium and reform runs through the rules, not the roster.


Public Interest Test

A doctrinal override on a default prohibition that permits otherwise-protected disclosure only when an institutional decision-maker weighs a qualifying social benefit against foreseeable harm and finds it outweighs — discriminating public interest from mere public curiosity.


Public-Key Cryptography

Give each party a mathematically linked public/private key pair where an operation done with one key is invertible only with the other and the private key cannot feasibly be computed from the public one, so confidentiality and verifiable authorship need no pre-shared secret.


Public Sphere

Habermas's communicative arena where private persons deliberate as a public about common concerns and form opinion that checks power — defined by four independent axes (access, autonomy, rational-critical mode, traction) that serve as a diagnostic grid across media systems and forums.


Public-Warning Fatigue

The emergency-communication failure in which a warning authority fires often enough, or with enough false positives, that the population habituates and discounts subsequent warnings — spending down a depletable, asymmetrically-rebuilt credibility budget.


Publication Bias

A scientific record becomes systematically unrepresentative when the probability that a study, result, or outcome becomes publicly available depends on its direction, magnitude, statistical significance, novelty, or sponsor-favoredness.


Purkinje Effect

Explain why red darkens and blue seems to glow at dusk: as light falls, the eye hands off from cones (peaking ~555 nm) to rods (peaking ~507 nm), so a whole different sensitivity curve — not the surfaces — reweights apparent brightness.


Quantity Theory of Money

Bind money supply, velocity, the price level, and real output in the identity MV = PY, then add the behavioural premises that velocity is stable and output is set by real factors — so that in the long run changes in the money stock translate proportionally into the price level.


Query Optimization

Let the author state only what result a declarative query should return, then have a separate optimiser search the space of algebraically equivalent execution plans and emit the cheapest one under a cost model.


Quote Laundering

A provisional but accurate statement is cited across successive venues that each strip its caveats and scope, until it circulates as authoritative settled fact — a channel failure, not a false source, so it resists source correction and needs traceability instead.


r/K Selection Theory

Predict a population's covarying demographic traits from how its environment divides a finite parental energy budget between offspring quantity and per-offspring investment — the r face for filling empty habitat fast, the K face for competing in a saturated one.


Random Variable

Translate an uncertain event into a measurable function X: Ω → ℝ on a probability space, so that a number attaches to each outcome and the whole apparatus of expectation, distribution, and convergence becomes computable before any value is observed.


Rank (Linear Algebra)

Read the effective dimensionality of a matrix or linear map as one integer — the number of linearly independent columns (equivalently rows) — so that solvability, invertibility, and reachability all reduce to comparing that count against a relevant dimension.


Rate-Limit Absence

Diagnose a whole family of endpoint abuses as one defect — a callable action left uncapped whose per-invocation cost to the service far exceeds the attacker's, so no enforced per-source budget separates legitimate demand from adversarial demand driven at machine speed.


Reader-Response

Treat meaning as co-produced in the act of reading rather than fixed in the text, and locate any divergence of readings at one of three sources — the text's gaps, the reader's horizon, or the interpretive community.


Real vs. Nominal Value Distinction

The operation of separating a monetary quantity's real change from the drift in its unit's purchasing power by dividing a nominal series through a price index and rebasing — treating the measuring unit itself as a variable, so cross-time comparisons are not confounded by inflation.


Rebound Emissions

An efficiency gain lowers both the per-unit emissions and the per-unit cost of an activity, and the cheaper cost stimulates more volume, partly or wholly offsetting the aggregate emissions reduction the efficiency would otherwise deliver.


Receiver Operating Characteristic

Sweep a binary classifier's decision threshold across its full score range to trace every achievable sensitivity-versus-false-positive-rate tradeoff at once, factoring detection into orthogonal discriminability (the curve's height) and criterion (where the threshold sits) coordinates.


Recency Effect

The empirical finding that the last items in a temporal sequence are recalled or weighted more heavily than middle items, driven by a short-term-store component and a temporal-distinctiveness component that a filled delay can separate.


Receptive–Expressive Language Profile

Assess language as two dissociable directional capacities — comprehension and production — and compare their separately measured levels, because the pattern of the gap localizes impairment and determines whether intervention targets input, output, or both.


Receptive Language

The comprehension arm of language capacity — receiving, parsing, and interpreting incoming linguistic input — defined in contrastive opposition to expressive (production) language, dissociable from it, and assessed on its own through an ordered processing stack with output held near zero.


Reconstructive Memory

Rebuild a remembered event at retrieval from incomplete traces, learned schemas, present cues, and later information rather than replaying a fixed record, so recall can remain coherent while its details, sources, and timing change.


Recovery Inequity

The disaster-management pathology in which the post-event restoration phase proceeds at systematically different speeds and end-state qualities across the affected population — because rebuilding is a distributive contest mediated by insurance, land tenure, political voice, and social capital, not a neutral reversion to baseline.


Red Herring

Deflect a discussion by introducing material irrelevant to the open question, so attention and the conversational floor shift to the new topic and the original question is left feeling-addressed-but-unanswered — the test being whether the new material does any work on the claim that was open.


Redistribution

The deliberate reallocation of income, wealth, or consumption between groups through state authority — a clearing-house collecting from a source base and paying a recipient base under rules set so the net flow runs from those with more to those with less along a named axis.


Abnormal Quality

Record an observed property not as a bare measurement but as a four-role assertion — bearer, quality, reference state, and deviation judgment — so that departures from expectation become directly queryable across heterogeneous traits.


Reflexive Journal

A dated, contemporaneous first-person record in which a qualitative researcher externalises the assumptions, commitments, and positional influences shaping each analytic decision — converting an unavoidable observer-effect into a documented variable an auditor can trace to confirmability.


Refused Bequest

Flag an inheritance edge as broken when a subclass accepts a parent's implementation but refuses part of its contract — stubbing, throwing, or silently mishandling inherited members — because that refusal is exactly the Liskov substitutability violation the is-a declaration promised not to make.


Regression

The statistical method of modelling an outcome as a systematic function of explanatory variables plus specified noise, fit by minimising a loss — supporting three distinct uses (prediction, effect estimation, variance attribution) each gated by its own validity conditions.


Regression Discontinuity Design

Recover a causal effect from a threshold rule by comparing units just above and just below a sharp cutoff on a continuous running variable, where they are comparable in expectation, so any jump in the outcome at exactly the cutoff is attributable to the treatment rather than to selection.


Regulatory Surprise

Name the venture failure in which a plan built on an assumed-stable rule environment is stranded when the rule moves, reframing that environment from a fixed constraint into a slow-moving but observable, monitorable variable.


Relational Model

Organize data as typed sets of tuples queried by a small closed algebra of relation-to-relation operators, so any composition is itself a valid query, rewrites preserve meaning, and the logical schema is separated from physical storage.


Relative Privation

The informal fallacy of dismissing a concern by pointing to a worse problem elsewhere, conflating severity-ranking with action-licensing — since ranking governs how much total attention a problem warrants, not whether it is eligible for any, unless the worse problem's resources are genuinely exclusive.


Publisher Relation

Collapse a long chain of authorship, review, and production into one resolvable metadata handle naming the agent who effected a resource's release, so every downstream governance question routes to the same addressable accountable party.


Reliability Paradox

Explain why tasks with robust group-level effects (Stroop, IAT) can be useless for ranking individuals: the design minimized within-subjects error for group power without guaranteeing the between-subjects variance that reliability, true-score over total variance, requires.


Rensch's Rule

The macroevolutionary regularity that sexual size dimorphism scales allometrically with body size across related species — the larger-on-smaller-sex slope exceeding 1.0 in male-larger clades and falling below 1.0 in female-larger ones.


Rent-Seeking Trap

The public-choice pathology in which institutional rules make the marginal return on capturing an existing rent exceed the return on producing new value, so effort is dissipated into contests over distribution — self-reinforcing where the rent-defending coalitions persist and manufacture further rents.


Repair Sequence

Resolve any conversational trouble by locating it in a small grid — trouble source, initiation, completion, crossed by who repairs (self or other) and where in the turn-sequence — and read the likely path to resolution off the preference for self-repair.


Repairability

The scored design property of a physical artefact measuring how cheaply and reliably a failed instance can be restored by component replacement rather than whole-unit replacement — a conjunction of accessible disassembly, modularity, documentation, parts availability, and software support.


Replacement Relation

Record that a distinct successor resource takes over a predecessor's canonical standing and flags it obsolete, as a bidirectional machine-routable link, so consumers read currency off the chain rather than inspecting the artifacts themselves.


Representativeness Heuristic

Judge how probable, frequent, or generatively plausible an outcome is by how closely it resembles a category prototype or expected process pattern, so typicality silently replaces the target quantity and becomes systematically misleading when base rates, sample size, or set inclusion disagree.


Request-Response

Treat any bounded network exchange as one shape — an initiator's addressed request causally paired to one responder's reply over a return path — so the same fixed checklist of addressing, correlation, retry, idempotency, and error handling applies regardless of payload.


Requirements Churn

A project pathology in which the specification changes faster than the execution organization can absorb it — a control-theoretic case where the reference signal outruns the controller's bandwidth, so no spec lives long enough for work to consolidate against it.


Requirements Volatility

Treat frequent, substantive change in a system's requirements as a measurable churn rate matched against the team's absorption capacity, then flatten Boehm's cost-of-change curve so late changes force only local rework rather than cascading redesign.


Resource Staging Failure

Diagnose a lost incident response as a marshalling-function breakdown, not a scarcity — resources present at the scene are undeployable because the ICS staging discipline that converts them from available to assignable is absent, so the fix is staging, not more resources.


Resource-Typing Mismatch

The incident-command failure where a mutual-aid requisition label ('ambulance,' 'swift-water team,' 'generator') is too coarse to pin the capability actually needed, so a faithfully-used label delivers the wrong point in its hidden capability range and misallocates resources at scale.


Responsive-Layout Breakage

Diagnose the silent UI failure where an interface's content survives a viewport, device, or locale transformation but its layout-encoded meaning — priority, adjacency, hierarchy, above-the-fold prominence — is lost, so a passing content-accessibility check actively conceals the defect.


Responsiveness channel

Turn vague openness to feedback into auditable accountability by requiring three co-occurring structures — a published intake surface, a documented response discipline, and a public decision log whose latency and rejection-with-reason rate anyone can read.


Restoration Baseline Error

Diagnose a restoration that targets a historical reference state no longer viable under shifted conditions — the error of treating the prior state as a fixed property of the place rather than a function of contemporaneous conditions that have themselves moved.


Retinotopy

Preserve the two-dimensional layout of the visual field as a two-dimensional layout on visual cortex — adjacent points in the world projecting to adjacent neurons — an invertible map that lets a lesion predict a scotoma and a rotating stimulus reconstruct the map.


Retrieval Facet

Expose one controlled descriptive dimension as an independently selectable and filterable axis whose values can be combined at query time with values selected on other axes.


Retrieval-Induced Forgetting

Recast retrieval as a selection operation in a competitive field: actively recalling some items from a shared-cue set inhibits the related-but-unretrieved competitors, leaving them measurably less recallable than if nothing had been practiced at all.


Retrieval Practice

Actively recalling information from memory produces stronger, more durable retention than an equivalent period of re-studying, because the effortful generative act of producing a target from a cue reconstructs and strengthens the memory trace more than passive re-exposure does.


Returns Friction

Diagnose why returns, recalls, and repairs move badly: the reverse flow is an irregular trickle of heterogeneous, quality-uncertain units forced through a network designed and optimized for one-directional forward flow, sharing its rails as an afterthought.


Revelation Principle

The mechanism-design theorem that any outcome achievable by any mechanism is also achievable by a direct mechanism where agents truthfully report their private type — collapsing the search over all mechanisms to a tractable optimization over incentive-compatibility constraints, while saying nothing about which mechanism to deploy.


Revenue Equivalence Theorem

The auction-theory result that under symmetric independent-private-values conditions, every format allocating to the highest bidder yields the seller the same expected revenue — pinning revenue to the allocation rule and lowest-type rent, so format matters only where a condition fails and the failure direction names the preferred format.


Reverse Logistics

Manage the backward flow of goods from consumption toward recovery through one invariant pipeline — receive, inspect-and-grade, route, settle — where the triage sorts each unit up a value gradient and the constraints invert the forward chain.


Review

A structured evaluative artifact linking four slots — an identified evaluator, a bounded object under evaluation, a verdict, and a warrant — into a persisted, addressable record, so evaluative testimony becomes aggregable, citable, and revisable.


Rhetorical Listening

Suspend rebuttal and parse another's discourse through three moves — what they claim as their stakes, what genuinely remains contested, and what your own position lets you hear — so an accurate hearing and a firm 'no' become compatible.


Rhetorical Question

Use interrogative form to perform an assertion rather than seek information, leaving the answer for the audience to supply internally so their self-generated agreement does the persuading — a move whose success rides entirely on an accurate audience model.


Rhetorical Situation

Read any occasion that calls a discourse forth through three slots — exigence, audience, and constraints — treating communication as a fit problem so that a misfit traces to a specific misread element rather than to a defect of craft.


Ricardian Equivalence

Treat a debt-financed tax cut as a deferred tax of equal present value, so forward-looking households save the windfall to meet the future bill and the financing choice adds no stimulus.


Rice's Theorem

Every non-trivial semantic property of programs — anything depending on the input-output function rather than the source text — is undecidable, proved by a generic reduction from the halting problem, so no exact analyzer for such a property can exist.


Riepl's Law

New communication media rarely make old ones extinct; instead the older medium re-specialises into the niches the newcomer fills poorly — depth, permanence, ceremony — producing a layered ecosystem in which both coexist at different roles.


Rift Zone

A region of lithosphere under extensional stress, where the crust thins by ductile flow and normal faulting and subsides as support is removed — a staged progression from doming through grabens to breakup whose maturity is captured by the McKenzie β-factor.


Ring

A set with two operations — an abelian group under addition and an associative multiplication coupled to it by the distributive law — whose axiom tier and ideal structure unlock a single body of theory (quotients, homomorphisms, factorization) across integers, polynomials, and matrices at once.


Risk-Free Rate Puzzle

The asset-pricing anomaly that a CRRA model calibrated to the observed equity premium predicts a real risk-free rate far above the ~1% seen — because the single parameter γ is overloaded as both risk aversion and the inverse elasticity of intertemporal substitution, so fitting one target misfits the other.


Risk Transfer Without Reduction

The maladaptation pattern in which an adaptation or defence lowers risk at a protected site by displacing the unchanged hazard onto a voiceless neighbour, catchment, or future generation — because it acts on one node's exposure rather than the generative pressure.


Riskiest Assumption Test

Rank a plan's assumptions by consequence-if-false times uncertainty times upstream-position, then spend the next effort on the cheapest credible test of the top one — the question whose answer would most reduce total wasted work.


Road Diet

Intentionally reduce a street's vehicle capacity and reallocate the recovered right-of-way to other uses — the classic four-to-three-lane conversion — because the throughput-maximising configuration sits below the joint optimum across safety, retail, and pedestrian function.


Robust Accessibility

Author web content so its load-bearing meaning lives in structural markup and the accessibility tree rather than in presentational accidents, so any current or future assistive technology — including ones the author cannot test against — can recover the intent through the same shared API.


Rondo Form

A large-scale musical structure that coheres by periodic return: a recurring principal theme (the refrain, A) in the tonic alternates with contrasting episodes (B, C, D) in related keys, yielding schemata like ABACA in which the refrain becomes the listener's memory.


Rules-of-Engagement Ambiguity

Diagnose frontline breakdown under time pressure as a grain mismatch — decision rules written coarser than the environment generates choice points — paid out of a finite discretion budget, relocating the fix from the operator's judgment to the rule, escalation path, and pre-positioned authority.


S&OP Disconnect

Diagnose a firm's downstream execution crises as an upstream planning defect — separate functions each holding an internally sound but mutually incompatible plan for the same future, because no binding forum reconciles them before commitments are taken.


Safety-Stock Illusion

Recognize that a buffer reported as adequate protection can be useless when disruption arrives, because effective protection is the weakest of five margins — size, location, composition, accessibility, and fit to the realised disruption — not the reported size alone.


Saga Pattern

Achieve all-or-nothing semantics across a multi-step operation that no single ACID transaction can span by pairing each local transaction with a forward compensating action, so a failure at step k runs compensations k-1 down to 1 and leaves the system as-if-nothing-happened.


Salience Network

Model a control network — anterior insula and dorsal ACC hubs — that detects behaviourally relevant events and switches the brain between its two content networks (internally directed default mode and externally directed executive), so cognition is read as a configuration plus a switching variable rather than a catalogue of regions.


Salinization

The process by which dissolved salts accumulate in soil, water, or an aquifer until they exceed tolerance thresholds — a salt-budget failure (input minus output over time) whose pathway sets the remediation and whose reversibility is asymmetric.


Salt Wedge

The wedge-shaped intrusion of dense saline water beneath a lighter freshwater outflow at an estuary mouth, whose sharp density interface tapers to a thin up-channel tip that migrates as an index of the river-versus-ocean force balance.


Say's Law (Supply Creates Its Own Demand)

The classical claim that aggregate production generates the income constituting aggregate demand, so a general glut cannot persist — a conditional resting on flexible market-clearing prices, no permanent hoarding, and a loanable-funds market that routes saving into investment.


Scale-Before-Fit

Diagnose a venture's failure as one of ordering — committing substantial growth investment before demonstrating repeatable, unsubsidised demand — by asking whether the evidence at the moment of commitment justified the cost base it locked in.


Schema Mapping Relation

Bridge two independently governed classification schemes with an explicit, typed assertion — source concept, target concept, and a fidelity grade (exact / close / broader / narrower / related) — so consumers know exactly what the bridge guarantees without merging the schemes.


Scope Neglect

Explain why elicited valuations stay flat across hundredfold changes in magnitude — the count is replaced by a single affect-laden prototype, so the number is understood but never priced in.


Screen-Reader Ambiguity

An interface's visual structure carries semantic information never encoded into the machine-readable accessibility tree, so an assistive-technology user — navigating only that projection — encounters an interface stripped of the organization a sighted user relies on.


Script Activation

Trigger, from a single environmental or linguistic cue, the loading of a stored ordered event sequence with role and prop slots and default fillers, which then gap-fills comprehension, pre-allocates processing, and scaffolds action at once.


Seamount Effect

Read submarine relief as a first-order control on ocean productivity via a fixed causal chain — relief plus flow yields a perturbation that mixes and upwells nutrients, raising production and aggregating life — that fires only when current, stratification, height, and latitude align.


Search Algorithm

Solve a problem by casting it as a state space explored with a frontier-ordering strategy, so completeness, optimality, and cost are read off the strategy's name — and an admissible heuristic buys a narrower search without sacrificing the optimal answer.


Hidden Label

A string attached to a controlled-vocabulary concept that is indexed for retrieval but withheld from display — so a user typing a typo, deprecated synonym, or embarrassing prior name finds the concept while the result still shows only the sanctioned preferred term.


Secret Sprawl

Diagnose a credential's danger not by whether its primary store is locked but by whether its copies have spread into more places than the issuer tracks, so revocability collapses and rotation cost scales with the unknown copy count.


Secular Stagnation

A structural glut of saving over investment pushes the market-clearing interest rate below zero — below the floor a central bank can reach — so rate cuts run out of room and the shortfall persists as deficient demand rather than the trend.


Sediment Budget

Account for sediment as a mass-balance ledger of sources and sinks over a bounded coastal or fluvial cell, so the running balance — not the last storm — tells whether the shoreline is accreting, stable, or eroding.


Sediment Transport

Loose grains are entrained by a moving fluid once shear exceeds their threshold of motion, carried in a mode set by the ratio of shear to settling velocity, and deposited as the carrier loses energy — sorting coarse-to-fine along the gradient into a graded deposit that records the flow.


Seismic Gap

Read prolonged silence on a fault segment as accumulated strain rather than safety — a renewal-process inference that ranks segments overdue against their recurrence interval as highest-hazard, valid only where segmentation and characteristic-recurrence hold.


Selection on Observables

Assume that, conditional on a named set of measured covariates, treatment assignment is independent of potential outcomes — so within each covariate stratum treated and untreated units are exchangeable and adjustment recovers the causal effect.


Self-Reference Effect

The memory phenomenon in which material encoded in relation to the self is recalled at higher rates than material encoded semantically, phonemically, or structurally — driven by the richness of the self-schema, so any comparably elaborated schema yields the same advantage.


Self-Serving Bias

The directional asymmetry by which agents credit their own successes to internal factors (ability, effort) and blame failures on external ones (luck, circumstance) to protect self-image — making any self-report about one's own outcome a biased evidence class with a known lean.


Sequential Clarity

Judge how well each item in an ordered presentation stands out not by its own quality but by how much it contrasts with its immediate temporal neighbours inside the working-memory window.


Sequential Compliance Technique

A requester deliberately stages an initial request or response-producing interaction so that its acceptance, refusal, or apparent concession changes the target's state and raises compliance with a later target request above the rate the later request would obtain alone.


Serial-Position Effect

The memory phenomenon in which items in a sequence are recalled in a U-shaped curve — high for the beginning (primacy, from extra rehearsal) and end (recency, from the transient buffer), sagging in the middle — with the two limbs mechanistically dissociable.


Server-Side Request Forgery

Diagnose the web attack in which an attacker-supplied URL makes a server issue a request under its own credentials and network position, by asking whether the issuer of the intent and the carrier of the authority are the same principal.


Service Level

Commit in advance to fulfilling a stated quantile of stochastic demand — not its average — within a stated window with a breach consequence, and size the system's buffer against that tail, so each additional nine costs disproportionately more reserve.


Service Recovery Paradox

The contingent finding that a customer who suffers an isolated failure and then receives a rapid, generous, authentic recovery can end up more loyal than one who had no failure — because a smooth transaction is diagnostically poor while a costly recovery signals competence and care the baseline could not.


Setup and Payoff

Place material early that a later development activates, so the payoff feels earned and the setup gains retrospective necessity; the relation requires both precedence and a relevant return.


Shannon–Hartley Theorem

Compute a noisy channel's maximum error-free bit rate as C = B·log₂(1 + S/N), a bound that is at once a wall no code can beat and a target codes can approach, linear in bandwidth but only logarithmic in signal-to-noise.


Shaping Operation

A military action whose purpose is to alter the conditions a later decisive operation will meet — degrading, suppressing, or deceiving the enemy field — so its value is realised through the field-state it produces, not through any objective it seizes itself.


Shelford's Law of Tolerance

Every organism has, for each environmental factor, a bounded tolerance range with two lethal limits, a central optimum, and two stress shoulders — so both deficiency and excess degrade performance, and persistence is gated by whichever factor sits closest to a limit.


Ship of Theseus

Expose that 'is it still the same thing?' has no brute answer once total component replacement pulls substrate-continuity apart from pattern-continuity — the verdict is relative to which identity criterion you have decided counts.


Side Reaction

An alternative chemical transformation running in parallel with the desired one, competing for the same substrate through its own rate law, so that selectivity — the ratio of desired rate to the sum of all competing rates — governs yield rather than the desired reaction's absolute speed.


Simile

A marked explicit comparison that transfers a single salient attribute from a familiar vehicle to an unfamiliar topic while keeping the two distinct, enabling fast perceptual or affective uptake.


Simon Effect

Explain why responses are faster when a stimulus's task-irrelevant spatial location matches the response side: the perceptual system pre-attentively generates a same-side response code that facilitates selection when it agrees with the task-mandated code and costs ~30 ms when it conflicts.


Single-Responsibility Principle

A module should have exactly one reason to change — read as one external change-driver, not one function — so that aligning each boundary with a single driver keeps every edit's blast radius contained.


Situated Cognition

Hold that knowing and skilled performance are constitutively of their situation — distributed across agent, tools, and setting — not a context-free program the situation merely modulates, forcing a constitutive-versus-causal test on any competence.


Situated Learning

Treat competence as something formed and recognised inside a community of practice rather than transferred through a curriculum, so a novice learns by doing real low-stakes work at the periphery and deepening toward the centre as the community recognises their growing skill.


Situational-Awareness Collapse

Locate a control failure under tempo in the picture-keeping pipeline rather than in missing data — a rate problem where perception, comprehension, or projection can no longer cycle fast enough to keep the decision-maker's model current.


Sleeper Effect

Explain why a message paired with a discounting cue can grow more persuasive over weeks: the persuasive content and the cue that braked it are stored as separate memory traces that decay at different rates, so when the cue fades faster the net persuasion inverts sign at delayed recall.


Slippery Slope

Flag a consequence-chain argument as fallacious when its inter-step links are held together only by conceivability rather than a demonstrated mechanism, so it blocks a proposal by gesturing at a speculative terminus.


Slutsky Decomposition

Decompose a price-induced change in consumer demand into a compensated substitution effect from changed relative prices and an income effect from changed real purchasing power, so the two terms sum exactly to the observed response.


Small-Study Effects

The meta-analytic pattern in which smaller studies report systematically larger effects than larger ones, producing funnel-plot asymmetry that inflates the pooled estimate — a shared symptom of several biases, not a diagnosis of any one cause.


Smoke Test

Probe demand for a product that doesn't exist yet with a cheap false-front — a landing page, pre-order, or fake door — that extracts a commitment-bearing signal, and build only if that signal clears a kill threshold set in advance.


Snob Effect

The demand pattern in which a consumer segment values a good more when fewer others own it — a negative prevalence term in utility that decomposes the good into a fixed use-value and a prevalence-dependent rarity signal.


Snowball Sampling

Recruit an unenumerable population by seeding a few participants and having each nominate others along their social ties, substituting relational proximity for random selection and buying access at the cost of representativeness.


Social Bonding

Explain why affectively capable individuals keep routing help and protection toward one another long after any incentive would predict it: repeated shared experience and emotional co-regulation forge a durable bond that generates behaviour above and orthogonal to current incentives.


Social Communication

Treat the relational-pragmatic layer of language — turn-taking, relevance, politeness, repair, register, common ground — as a layer distinct from grammatical correctness that can fail on its own, so a child with clean syntax may still be unable to hold a conversation.


Social Presence

The felt sense of being together with another social actor through a medium — a variable distinct from transmission fidelity, jointly produced by cue inventory, self-disclosure, turn-taking synchrony, and individual recognition, and upstream of engagement, trust, learning, and retention.


Social Surplus

Measure a market's total net benefit as the area between the demand and supply curves — consumer plus producer surplus — so a policy's efficiency cost reads off the deadweight-loss triangle of trades the price wedge suppresses, distinct from surplus merely transferred.


Software Entropy

Read a codebase's growing structural disorder as a predictable gradient under continuous modification: locally expedient edits flow toward the vast basin of working-but-disordered states, and order decays monotonically unless restoring engineering effort is continuously reinjected.


Soil formation

Model a soil profile as a function of five interacting drivers — climate, organisms, relief, parent material, and time — so that holding four fixed and varying one lets the landscape run a controlled experiment, with the horizon sequence recording which processes dominated and for how long.


Solow Computer Paradox

The puzzle that heavy IT investment coincided with a productivity slowdown, not an acceleration — resolved as a deployment-to-impact lag: the headline measure waits on the complementary intangible stocks (process redesign, retraining, standards) a general-purpose technology must accumulate first.


Solow–Swan Model

The neoclassical growth model whose diminishing-returns structure drives each economy to a parameter-pinned steady state, yielding conditional convergence — economies sharing fundamentals close their gaps at a rate set by the capital share, while saving raises the level of income but not the long-run growth rate.


Solubility

Specify the maximum amount of a solute that can dissolve in a solvent as a function of temperature, pressure, pH, and ionic strength — the equilibrium point where dissolved and undissolved chemical potentials equalize and net transfer ceases.


Somatotopy

Represent the body surface on neural tissue as a continuous neighbourhood-preserving map — adjacent body regions projecting to adjacent neural loci — with magnification set by receptor density and behavioural importance rather than body size, and reshaped by an activity-dependent plasticity rule.


Sonata Form

Organise a movement as a tonal journey out of the home key and back — exposition posing a conflict when the second theme sounds abroad, development intensifying it, recapitulation healing it by bringing that theme home — so closure is reconciliation, not mere stopping.


Sorting Algorithm

A computational procedure that rearranges a finite sequence into a specified total order, located in a coordinate space of complexity, stability, and memory, and bounded below by the Ω(n log n) decision-tree floor for comparison-based sorts.


Source Credibility

A receiver-side, perception-mediated weighting attached to a communicator — decomposing into expertise, trustworthiness, and goodwill — that gates how much of a message's content is accepted and acted upon, independent of the content's own evidential quality.


Source Protection

The layered practice by which a journalist shields a vulnerable upstream provider's identity from any party who would harm them — protecting not just the present source but the future channel, since a single breach collapses the protection promise across every source not yet contacted.


Sourcing Ladder

Rank the sources backing a claim by directness, independence, expertise, and accountability, then resolve disagreements by letting the higher rung win and cap a chain's confidence at its weakest load-bearing link.


Space syntax

Represent a spatial layout as a graph of sight-and-movement lines and compute centrality measures like integration and choice, so a space's pedestrian use, vitality, and encounter rates are predicted from its configurational position rather than its local design.


Spaghetti Code

Diagnose a codebase as unmaintainable by reading its dependency graph: when boundary-violating edges accumulate past a threshold, the cost of any local change scales with the whole system rather than the unit being changed.


Spatial coverage

A metadata declaration publishing the geographic region within which a resource is valid — an explicit inclusion-exclusion rule on the spatial dimension that lets the catalog check, before any analysis, whether a question's scope falls inside or outside it.


Spatial Updating

Keep the surrounding layout accurate as you move by integrating self-motion signals into an estimate of how your viewpoint has changed and applying that transformation to every stored object location, no fresh look required.


Special Pleading

The fallacy of exempting a favored case from a general standard the arguer just invoked, without a principled basis — a consistency violation under self-serving direction, exposed by asking whether the arguer would grant the same exception to an opponent.


Species–Area Relationship

The empirical power law S = cA^z by which species count rises sublinearly with area — so its exponent z diagnoses the operative mechanism and, inverted, turns habitat-area loss into a predictable (and deceptively gentle) committed species loss.


Speculative Generality

Diagnose a design that carries flexibility for imagined future variation not yet justifying its cost by pricing each abstraction as an unexercised option — with no named consumer, credible timeline, or second concrete instance, it is overhead masquerading as foresight.


Spike-Timing-Dependent Plasticity

A synaptic learning rule where the sign of a weight change depends on the millisecond order of pre- and postsynaptic spikes — pre-before-post potentiates, post-before-pre depresses — turning a coincidence detector into a causality detector that grows directed connectivity.


Split-Brain Problem

The distributed-systems failure where a network partition splits a replicated cluster into subsets that each elect themselves as write authority and accept divergent writes; guard against it by enforcing that at most one subset — the quorum majority — may write.


Spotlight Effect

Explain the felt certainty that everyone noticed as an estimation error: the actor anchors on how salient a self-feature is from the inside and under-corrects toward observers' far lower base-rate attention, so predicted notice runs about double the actual.


Spotlight Fallacy

Infer that a property is common in a population because it is prominent in coverage of it — mistaking a selection bias for a base rate, since an attention-allocating channel surfaces cases by newsworthiness rather than by frequency.


St. Petersburg Paradox

A gamble whose expected monetary value is infinite yet which real deciders will pay only a few coins to enter, exposing that a value function linear in money mishandles fat-tailed payoffs and must be replaced by a concave or bounded utility.


Stag Hunt

Model a cooperation problem in which the joint payoff-dominant choice and a certain safe choice are both equilibria, so the barrier to cooperating is not temptation but coordination under uncertainty about the partner — fixed by assurance, not enforcement.


Staging Area

Hold prepared resources in a ready-to-deploy state in a zone adjacent to the point of need but outside the active flow, so preparation cadence and consumption cadence can each run at their own rate across one buffer.


Standard of Care

Use the currently accepted reference practice as the single dynamic baseline against which both efficacy (is a treatment better than what we already do?) and accountability (did a clinician meet what a reasonable body of practitioners would have done?) are measured by deviation.


State-Dependent Learning

The memory phenomenon in which material encoded in one internal physiological or psychological state is retrieved more reliably when the agent is again in a matching state — because the body's condition at learning is bound into the trace as part of the encoding context — diagnosed by a crossover interaction where matched states beat mismatched ones.


Status Quo Bias

Model the systematic over-choosing of whatever option is framed as current — the same two alternatives chosen at different rates depending only on which is the default — as a content-independent departure surcharge built from loss aversion, regret aversion, and decision cost.


Status Quo Trap

Frame status quo bias as a named trap a single deliberating actor can counter: recognise that the current course wins only because the switch must be defended while the staying is not, then run the fresh-start counterfactual that forces it to compete on its merits.


Stein's Paradox

The result that estimating three or more means each by its own sample mean is inadmissible under total squared-error loss — a shrinkage estimator pulling each toward a common reference achieves strictly lower joint error for every true parameter vector, however unrelated the quantities.


Stereotype Threat

The situational performance drop that occurs when a negative group stereotype is made salient in an evaluative setting, consuming the working-memory capacity the task itself requires.


Stevens's Power Law

Relate the perceived magnitude of a sensation to the physical intensity of the stimulus by a power function ψ = k·I^β, whose modality-characteristic exponent β compresses the sense (β < 1), expands it (β > 1), or leaves it near-linear — recovered as the slope of magnitude estimates plotted on log-log axes.


Stimulus–Response Compatibility

When a stimulus automatically activates a response code, performance improves if that code agrees with the task-mandated response and degrades if the codes conflict, even when the triggering feature is irrelevant.


Stockout

Pin inventory's central failure to a precise binary event — on-hand stock for one SKU at one location reaching zero while demand still arrives — whose heterogeneous, mostly-unobservable cost, weighed against holding cost, drives every safety-stock and service-level decision.


Stoichiometry

Fix the exact amounts of reactants consumed and products formed from a balanced equation's integer molar ratio and conserved mass, so the reactant shortest in proportion — the limiting reagent — alone caps the theoretical yield.


Strain Localisation

Distributed deformation becomes unstable and concentrates into a narrow band because local deformation changes the material or geometry in a way that attracts still more strain, creating a self-focusing path toward necking, shear banding, faulting, or breakup.


Strangler Fig Pattern

Replace a legacy system incrementally in place by fronting it with a stable interception layer, rerouting one validated request path at a time to the replacement, and retiring the legacy once nothing routes to it.


Straw Man

Refute a weakened proxy of an opponent's view instead of the view they actually hold, so an apparent victory leaves the real position untouched.


Stream Processing

Compute over data as it arrives — one record or small time-window at a time — under a bounded-latency commitment, decoupling when an event happened from when it arrived and using a watermark to decide when a time window is safe to close and emit.


Strong Consistency

Guarantee that every read of a replicated store reflects the most recently completed write and all clients see one real-time-consistent total order (linearizability), so the system can be reasoned about as a single copy — bought with a coordination round and partition-time unavailability.


Stroop Effect

Measure cognitive control by the extra time and errors it costs to name a color word's ink when the word disagrees — a competition between an over-trained automatic pathway and a weaker task-relevant one, resolved by top-down inhibition.


Strophic Form

The song structure in which every verse reuses one invariant musical frame — melody, harmony, accompaniment, phrase lengths — while only the lyric text changes, so the constant backdrop foregrounds the varying words as variations against it.


Structuralism

Analyse meaning in a system as determined by the relations among its elements rather than their intrinsic properties — defining each unit by what it is not, bracketing history, and recovering the small latent relational grammar that generates a corpus's large surface variety.


Stuttering

A neurodevelopmental fluency disorder of atypical speech-motor coordination, structured as layers — involuntary primary disfluencies (repetitions, prolongations, blocks), a partly-learned avoidance overlay, and a self-concept dimension — where diagnosis and treatment turn on which layer carries the disability.


Subadditivity Effect

Diagnose why the judged probability of an event named as a whole comes in reliably below the sum of judged probabilities for its named parts — because unpacking recruits more cognitive support — reading the known upward sign off which figure was solicited packed versus partitioned.


Subduction

Explain a whole catalogue of convergent-margin phenomena — trench, volcanic arc, deep earthquakes, mountain-building — as expressions of one cold dense lithospheric plate sinking into the mantle, driven by density contrast and self-sustained by slab pull.


Subduction Zone

The convergent plate boundary at which a denser plate descends into the mantle along a dipping megathrust, coupling trench, great earthquakes, arc volcanism, prism, and back-arc deformation to one slab — so a margin's whole hazard suite reads off a few slab parameters.


Subgame Perfect Equilibrium

Refine the Nash equilibria of a sequential game by keeping only strategy profiles that prescribe a best response in every subgame, discarding outcomes propped up by threats a player would never actually carry out.


Subject-Expectancy Effect

Treat a participant's beliefs about an intervention as a genuine driver of their reported and physiological responses, so any unblinded measurement confounds the manipulation with anticipation until blinding, placebo control, or a balanced-placebo design pulls the two apart.


Subsidence

Explain the downward descent of the ground surface as loss or rearrangement of subsurface support, routed through one channel — a change in the Terzaghi effective-stress state — so any driver's cause and reversibility read off a single ledger.


Subsidence Basin

Read a region's buried history by treating it as a lithospheric floor that lowered — its shape diagnosing the mechanism and the supply-to-subsidence ratio setting how it filled — so the preserved strata can be run backward to thermal, tectonic, and erosional history.


Substitution Effect

Isolate the part of a consumer's demand response to a price change that comes purely from shifted relative prices, holding real purchasing power constant, by hypothetically compensating income and observing how she reallocates toward the now-cheaper goods.