{"schema":"https://ver.cy/schemas/card/1.0.0","id":"vr.tr.common-knowledge","code":"thing-q1116133","url":"https://ver.cy/models/thing/q1116133/","name":"common knowledge","alternateNames":[],"kind":"thing","status":"published","version":"0.1.0-research.1","language":"en","classifiers":{"family":"Thing Registry","category":"Information and virtual systems","entryKind":"thing","plane":"INF","domain":["INF.KNW"],"industry":[],"navPath":"","tags":[],"facets":{}},"whatItIs":"Common knowledge is information generally taken to be known within a community and, in formal epistemology and game theory, a proposition that everyone in a specified group knows, everyone knows that everyone knows, and so on through every finite level of mutual knowledge.","purpose":"Enable an agent to distinguish widespread familiarity from common knowledge within a specified group and assess whether coordination may rely on it.","scope":{"in":["The proposition or rule said to be common knowledge and its intended interpretation","The group, membership boundaries and time to which the claim applies","The distinction between widespread familiarity, everyone knowing and recursive mutual knowledge","Public communication and shared observation that may establish common knowledge under stated assumptions","Evidence, uncertainty and changes affecting reliance on common knowledge"],"out":["Individual knowledge acquisition and memory except where they support a group-level claim","The general truth evaluation of propositions independently of their distribution and recognition","Common sense as a capacity for practical judgment","Collective intelligence and methods for aggregating distributed information","Social norms, legal obligations and conventions beyond their status as commonly known","The disciplines of epistemology, epistemic logic and game theory themselves"],"boundaries":[]},"distinguishingFeatures":["A common-knowledge claim identifies a group and proposition; an unqualified statement that something is obvious does not establish either.","In the formal sense, everyone knowing a proposition is insufficient: everyone must know that everyone knows it, and so on through every finite depth.","Formal common knowledge concerns knowledge, so unanimous acceptance of a false proposition can be common belief but cannot be common knowledge.","Public availability of information does not establish that group members received it or recognize one another's access and understanding.","Everyday common knowledge can mean widespread familiarity without satisfying formal recursive conditions; the intended sense must be explicit."],"structure":{"bundles":[{"id":"content-and-meaning","name":"Content and meaning","description":"Identify exactly what is said to be common knowledge and which meaning of the term applies.","layers":[{"id":"sense-selection","name":"Sense selection","description":"Separate everyday familiarity claims from formal epistemic claims.","findings":[{"id":"intended-commonness","name":"Intended commonness","description":"Record whether commonness means broad distribution or recursively recognized knowledge.","questions":[{"text":"Does common knowledge here mean widespread familiarity or knowledge shared through every finite level of mutual awareness?","id":"intended-commonness-q01","kind":"definition"},{"text":"If the everyday sense is intended, which audience and familiarity threshold make the claim meaningful?","id":"intended-commonness-q02","kind":"boundary"}]}]},{"id":"proposition-alignment","name":"Proposition alignment","description":"Resolve the content and interpretation shared by the group.","findings":[{"id":"same-proposition","name":"Same proposition","description":"Distinguish common wording from agreement on referents, conditions and meaning.","questions":[{"text":"What exact proposition, including time and contextual qualifiers, is said to be commonly known?","id":"same-proposition-q01","kind":"definition"},{"text":"What evidence supports that members understand the same proposition rather than merely recognize the same expression?","id":"same-proposition-q02","kind":"provenance"}]}]}]},{"id":"group-and-recursion","name":"Group and recursion","description":"Specify whose knowledge counts and how higher-order awareness is assessed.","layers":[{"id":"membership-boundary","name":"Membership boundary","description":"Identify the agents included in the claim and their recognition of the relevant group.","findings":[{"id":"reference-group","name":"Reference group","description":"Make membership explicit enough to test statements about everyone in the group.","questions":[{"text":"Which agents belong to the reference group at the time of assessment?","id":"reference-group-q01","kind":"boundary"},{"text":"What do members know about who else belongs, and how does uncertainty about membership affect this claim?","id":"reference-group-q02","kind":"measurement"}]}]},{"id":"higher-order-awareness","name":"Higher-order awareness","description":"Track the difference between everyone knowing and everyone knowing that everyone knows.","findings":[{"id":"recursive-support","name":"Recursive support","description":"Record the supported depth of mutual knowledge and any justification for an unbounded formal condition.","questions":[{"text":"Which levels of nested knowledge are supported, and where does the evidence stop?","id":"recursive-support-q01","kind":"measurement"},{"text":"What formal argument or model assumptions justify common knowledge beyond any finite series of confirmations?","id":"recursive-support-q02","kind":"provenance"}]}]}]},{"id":"public-establishment","name":"Public establishment","description":"Examine how communication or observation could make knowledge mutually recognizable.","layers":[{"id":"announcement-conditions","name":"Announcement conditions","description":"Assess the publicness, reception and interpretation of an establishing event.","findings":[{"id":"public-event-support","name":"Public event support","description":"Record the conditions under which an announcement or observation supports higher-order awareness.","questions":[{"text":"Which event exposed the proposition to the group, and what evidence supports reception and comprehension?","id":"public-event-support-q01","kind":"provenance"},{"text":"What makes the event's occurrence and its accessibility to others mutually recognizable?","id":"public-event-support-q02","kind":"measurement"}]}]},{"id":"communication-limits","name":"Communication limits","description":"Identify delivery uncertainty and private information that interrupt recursive awareness.","findings":[{"id":"acknowledgment-gap","name":"Acknowledgment gap","description":"Assess what receipts and confirmations establish without treating finite exchanges as automatically sufficient.","questions":[{"text":"Can messages or acknowledgments be lost, delayed, hidden from some members or interpreted differently?","id":"acknowledgment-gap-q01","kind":"boundary"},{"text":"What additional shared observation or channel assumptions would support the epistemic condition required for the task?","id":"acknowledgment-gap-q02","kind":"action"}]}]}]},{"id":"truth-and-warrant","name":"Truth and warrant","description":"Separate knowledge from belief and distinguish evidence from formal idealization.","layers":[{"id":"knowledge-versus-belief","name":"Knowledge versus belief","description":"Assess whether the content and agents' epistemic positions support a knowledge claim.","findings":[{"id":"factivity-check","name":"Factivity check","description":"Keep truth support separate from evidence that people accept a proposition.","questions":[{"text":"What supports the truth of the proposition independently of how widely it is accepted?","id":"factivity-check-q01","kind":"provenance"},{"text":"Does the available evidence support knowledge, common belief or only a shared report?","id":"factivity-check-q02","kind":"boundary"}]}]},{"id":"assessment-basis","name":"Assessment basis","description":"Expose assumptions and observational limits behind the assigned status.","findings":[{"id":"evidence-and-idealization","name":"Evidence and idealization","description":"Distinguish observed behavior from claims established only within an epistemic model.","questions":[{"text":"Which parts of the assessment come from observation, participant reports or a formal derivation?","id":"evidence-and-idealization-q01","kind":"provenance"},{"text":"Which assumptions about reasoning, memory, interpretation and shared channel knowledge are needed for the conclusion?","id":"evidence-and-idealization-q02","kind":"boundary"}]}]}]},{"id":"reliance-and-reassessment","name":"Reliance and reassessment","description":"Connect the assessed condition to coordination and track changes that affect its applicability.","layers":[{"id":"coordination-requirement","name":"Coordination requirement","description":"Identify the actual level of shared awareness needed for a proposed action.","findings":[{"id":"reliance-threshold","name":"Reliance threshold","description":"Match the task's informational requirement to the strength of the common-knowledge assessment.","questions":[{"text":"Which proposed action depends on members knowing that others know this proposition?","id":"reliance-threshold-q01","kind":"action"},{"text":"Does that action require formal common knowledge, a finite awareness depth or sufficiently widespread familiarity?","id":"reliance-threshold-q02","kind":"boundary"}]}]},{"id":"change-and-repair","name":"Change and repair","description":"Monitor membership, content and epistemic changes that require renewed assessment.","findings":[{"id":"reassessment-triggers","name":"Reassessment triggers","description":"Record conditions under which a previous common-knowledge claim no longer supports present reliance.","questions":[{"text":"Have new members, forgetting, revised information or changed referents undermined the earlier assessment?","id":"reassessment-triggers-q01","kind":"measurement"},{"text":"What renewed announcement, shared observation or revised coordination procedure would restore sufficient support?","id":"reassessment-triggers-q02","kind":"action"}]}]}]},{"id":"evidence-and-external-alignment","name":"Evidence and external alignment","description":"What the world already says about this thing, gathered so the model can be checked against it.","layers":[{"id":"reported-evidence","name":"Reported evidence","description":"Findings from the breadth pass, kept separate from the structural claims.","findings":[{"id":"evidence-confidence-notes","name":"Check these first","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these check these first hold for the sense of common knowledge this model covers, and on what evidence?","id":"evidence-confidence-notes-q01","kind":"provenance"}]},{"id":"evidence-kinds","name":"Kinds and varieties","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these kinds and varieties hold for the sense of common knowledge this model covers, and on what evidence?","id":"evidence-kinds-q01","kind":"provenance"}]},{"id":"evidence-real-world-use","name":"Real-world use","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these real-world use hold for the sense of common knowledge this model covers, and on what evidence?","id":"evidence-real-world-use-q01","kind":"provenance"}]},{"id":"evidence-failure-modes-and-hazards","name":"Failure modes and hazards","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these failure modes and hazards hold for the sense of common knowledge this model covers, and on what evidence?","id":"evidence-failure-modes-and-hazards-q01","kind":"provenance"}]},{"id":"evidence-regional-variation","name":"Regional variation","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these regional variation hold for the sense of common knowledge this model covers, and on what evidence?","id":"evidence-regional-variation-q01","kind":"provenance"}]},{"id":"evidence-neighbours","name":"Neighbouring kinds and how to tell them apart","description":"Recalled without web access and unsourced; every item is a lead to verify.","questions":[{"text":"Which of these neighbouring kinds and how to tell them apart hold for the sense of common knowledge this model covers, and on what evidence?","id":"evidence-neighbours-q01","kind":"provenance"}]}]}]}]},"agentConduct":{"may":["Explain common knowledge in its everyday and game-theoretic senses, keeping them apart.","Note which community a claim of common knowledge assumes."],"mustNot":["Present a contested or false claim as common knowledge to avoid citing evidence.","Assume that something widely known in one culture or group is known to everyone.","Treat information as common knowledge to justify publishing private data about a person.","Confuse mutual knowledge with full common knowledge in formal analysis."],"requiresHuman":["Relying on an assumption of common knowledge in a legal notice or safety warning."]},"ethics":{"considerations":["Calling something common knowledge can shut down questions and exclude outsiders.","Assuming shared knowledge can leave vulnerable people uninformed of risks."],"affectedParties":["Newcomers and minorities","Readers relying on the claim"]},"owners":{"steward":"Nobody owns the concept; each community holds its own common knowledge.","roles":[],"masterSystems":[]},"relations":[{"target":"Q9081","type":"parent","note":"registry parent class"}],"interaction":{"identity":{"applicability":"required","items":["Vercy registry: vr.tr.common-knowledge","Wikidata: Q1116133 (https://www.wikidata.org/wiki/Q1116133)"]},"properties":{"applicability":"not-applicable","items":["Intended sense: formal common knowledge | everyday widespread knowledge | unresolved","Propositional content: Link to a proposition with its referents, interpretation and temporal qualifiers","Reference group: Explicit agents or a membership rule with relevant exclusions","Recursive depth supported: Nonnegative integer depth; unbounded only under an explicit formal justification; otherwise unknown","Truth status of content: supported as true | contested | false | unresolved","Establishment mechanism: public announcement | shared observation | established convention | repeated interaction | inferred familiarity | unknown","Epistemic assessment: claimed | supported to finite depth | established within a formal model | refuted | unresolved","Applicability interval: Time interval and events requiring reassessment"]},"recognition":{"applicability":"not-applicable","items":[]},"capabilities":{"applicability":"required","items":["Disambiguate whether a claim means widespread familiarity or formal common knowledge.","Assess a specified proposition and group against explicit recursive-awareness requirements.","Identify missing reception, comprehension or mutual-awareness evidence before a coordinated action.","Design a public announcement or shared observation around the assumptions needed for the intended epistemic result.","Reassess a claim after membership, communication or content changes.","Choose whether to rely on the claim, obtain further confirmation or use a procedure requiring less shared knowledge."]},"hazards":{"applicability":"required","items":["Treating a widely repeated falsehood as established truth can spread misinformation and support poor decisions.","Assuming that everyone shares the same background knowledge can exclude participants or undermine coordination.","Labeling a contested claim as common knowledge can discourage necessary verification."]},"interfaces":{"applicability":"not-applicable","items":[]},"context":{"applicability":"required","items":["Common knowledge is invoked in conversation, education and public discussion for statements considered widely known within a community.","It helps speakers judge which background information may be left unstated.","Whether a statement qualifies depends on the audience and context, and widespread acceptance alone does not establish its truth."]}},"sources":[{"title":"Wikidata item Q1116133: common knowledge","url":"https://www.wikidata.org/wiki/Q1116133","note":"identity and sense of the item"},{"title":"Wikipedia: Common knowledge","url":"https://en.wikipedia.org/wiki/Common_knowledge","note":"general description of the item"}],"openQuestions":["Does the registry intend the formal epistemic concept, the everyday sense of widely known information or both?","Does an existing world model already own common knowledge or a broader epistemic condition to which this entry should link?","Which authoritative treatments should govern the distinction between common knowledge, common belief, mutual knowledge and conversational common ground?","What evidence standard should permit an empirical claim of common knowledge rather than finite-depth support or establishment within an idealized model?","Should approximate or probabilistic forms of common knowledge be represented here, or linked as distinct concepts after their boundaries are researched?"],"resources":{"spec":"/models/things/publications/thing-q1116133/spec.json"},"provenance":{"origin":"thing registry research (pass 2)","builtFrom":["models/things/publications/thing-q1116133/spec.json"],"providers":["Codex"],"researchStatus":"unreviewed","generatedAt":"2026-09-12T08:48:12Z","builder":"tools/build_cards.py@1.0.0"},"completeness":{"sections":{"classifiers":"filled","whatItIs":"filled","purpose":"filled","distinguishingFeatures":"filled","structure":"filled","agentConduct":"filled","ethics":"filled","owners":"filled","relations":"filled","interaction.identity":"filled","interaction.properties":"not-applicable","interaction.recognition":"not-applicable","interaction.capabilities":"filled","interaction.hazards":"filled","interaction.interfaces":"not-applicable","interaction.context":"filled","sources":"filled"},"notes":{"_gate":"Published through the thing publication gate 1.0 on 2026-10-09T07:29:58+00:00: completeness 1.00; sense: Wikidata description; 2 live sources; review by codex: pass","interaction.properties":"Plane INF: no invented physical properties.","interaction.interfaces":"No generally applicable standard, law or official classification governs whether a statement is common knowledge in this sense.","interaction.recognition":"Common knowledge is an informational status within a community and has no directly observable visual features."},"score":1.0}}