{ "model": { "rank": 7383, "code": "thing-q216866", "model_id": "vr.tr.conjoined-twins", "name": "conjoined twins", "purpose": "Let an agent explain conjoined twins and their classification respectfully and in general terms from medical sources, describe causes, care and separation decisions, relay history and notable cases with dignity, and route families to specialist centres.", "family": "Thing Registry", "category": "Cross-cutting context", "status": "research-draft", "kind": "thing", "plane": "XCT", "domain": "XCT.STA", "industry": "", "version": "", "url": "/models/thing/q216866/", "tier": 2, "score": 55, "payload": { "layer": "wikidata", "aliases": [ "monozygotic conjoined twins", "dizygotic conjoined twins", "Ischiopagi", "polycephaly", "dicephalic parapagus twins", "conjoined animal twins", "craniopagus twins", "Craniopagus parasiticus" ], "aliasCount": 8, "merged": 8, "knownIn": 55, "facets": null, "markers": [], "lexicalClass": "", "senseRank": null, "alsoRegisteredAs": null, "source": { "dataset": "wikidata", "item": "Q216866", "url": "https://www.wikidata.org/wiki/Q216866", "license": "CC0 1.0" } }, "research": { "vercy": "1.0-draft", "publication": { "status": "research-draft", "adjudicationStatus": "unreviewed", "publishableCanonical": false, "generatedAt": "2026-09-13T04:40:26Z", "providers": [ "Claude" ], "breadth": "written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify", "pass": 2, "wave": 3, "engine": "claude" }, "metaModel": { "id": "THING-Q216866", "registryId": "vr.tr.conjoined-twins", "name": "conjoined twins", "version": "0.2.0-wave.3", "entryKind": "thing", "family": "Thing Registry", "domain": [ "XCT.STA" ], "status": "research-draft" }, "canonicalUrl": "https://ver.cy/models/thing/q216866/", "model": { "registry_id": "vr.tr.conjoined-twins", "name": "conjoined twins", "purpose": "Let an agent explain conjoined twins and their classification respectfully and in general terms from medical sources, describe causes, care and separation decisions, relay history and notable cases with dignity, and route families to specialist centres.", "definition": "Identical twins whose bodies are joined at birth, arising when a single fertilised egg fails to separate completely, classified by the site of union such as thoracopagus at the chest, omphalopagus at the abdomen, ischiopagus at the pelvis, craniopagus at the head, and dicephalic parapagus with two heads on one body, with polycephaly as the general term for multiple heads; conjoined twinning also occurs in animals, and separation surgery, when possible, depends on shared organs and raises medical and ethical questions.", "what_it_is_for": "Not applicable; a condition.", "affordances": [ "explain classification and causes", "relay care and separation", "relay history respectfully", "route families" ], "distinguishing_features": [ "Incomplete monozygotic separation", "Classification by union site", "Shared organs", "Complex separation decisions" ], "appearance": "Not a visible object; twins physically joined at a shared region.", "visual_identification": [ "Physically joined identical twins", "Thoracopagus, omphalopagus, ischiopagus, craniopagus, dicephalic parapagus; polycephaly; conjoined animal twins", "Monoamniotic twins share a sac but are separate; parasitic twins are asymmetric forms" ], "physical_properties": [ { "quantity": "incidence", "typical_range": "about 1 in 50000 to 200000", "unit": "births", "note": "estimates" }, { "quantity": "female share", "typical_range": "about 70", "unit": "percent", "note": "" }, { "quantity": "most common type", "typical_range": "thoracopagus", "unit": "type", "note": "about 40 percent" } ], "families_and_kinds": [ "thoracopagus and omphalopagus twins", "ischiopagus and pygopagus twins", "craniopagus twins", "dicephalic parapagus twins", "parasitic and heteropagus twins", "polycephaly in animals and conjoined animal twins", "historical claims of dizygotic conjoined twins, considered doubtful" ], "related_models": [ { "relation": "is a kind of", "target": "monoamniotic twins", "why": "in registry terms" }, { "relation": "is a kind of", "target": "diseases in twins", "why": "in registry terms" }, { "relation": "arises from", "target": "monozygotic twins", "why": "with incomplete separation" }, { "relation": "may be treated by", "target": "separation surgery", "why": "when feasible" } ], "identifiers": [ { "scheme": "ICD-11", "value_or_pattern": "LD2F.0", "note": "conjoined twins" }, { "scheme": "MeSH", "value_or_pattern": "D014428", "note": "twins, conjoined" } ], "standards_and_regulation": [ "Paediatric surgical and ethical guidelines on separation", "Prenatal diagnosis and counselling standards", "Disability rights and dignity frameworks" ], "failure_modes_and_hazards": [ "Sensational or disrespectful presentation", "Agents giving personal medical advice", "Presenting ethical debates as settled" ], "in_scope": [], "out_of_scope": [], "characteristics": [] }, "sources": [], "structure": { "bundles": [ { "id": "understand", "name": "Understand", "description": "What conjoined twins are.", "rationale": "Clinical.", "layers": [ { "id": "definition", "name": "Definition", "description": "Definition and causes.", "findings": [ { "id": "definition-finding", "name": "Definition", "description": "Definition.", "questions": [ { "text": "What are conjoined twins, and how do they arise from incomplete separation of monozygotic twins?", "kind": "definition" }, { "text": "Is the question about conjoined twins, other twin types or animal cases?", "kind": "boundary" } ] } ] }, { "id": "types", "name": "Types", "description": "Classification.", "findings": [ { "id": "types-finding", "name": "Types", "description": "Types.", "questions": [ { "text": "How are twins classified by union site, from thoracopagus and ischiopagus to craniopagus and dicephalic parapagus?", "kind": "definition" }, { "text": "Which entry fits the specific type?", "kind": "action" } ] } ] } ] }, { "id": "care", "name": "Care", "description": "Care and separation.", "rationale": "Clinical.", "layers": [ { "id": "diagnosis", "name": "Diagnosis", "description": "Diagnosis and planning.", "findings": [ { "id": "diagnosis-finding", "name": "Diagnosis", "description": "Diagnosis.", "questions": [ { "text": "How are conjoined twins diagnosed prenatally and assessed for shared organs?", "kind": "provenance" }, { "text": "Is the user asking about a specific pregnancy or family, which needs specialist clinicians?", "kind": "boundary" } ] } ] }, { "id": "separation", "name": "Separation", "description": "Separation surgery.", "findings": [ { "id": "separation-finding", "name": "Separation", "description": "Separation.", "questions": [ { "text": "When is separation attempted, what are the outcomes, and what ethical questions arise, with positions attributed?", "kind": "provenance" }, { "text": "Is the presentation respectful and attributed?", "kind": "boundary" } ] } ] } ] }, { "id": "living", "name": "Living", "description": "Living conjoined.", "rationale": "Attribution.", "layers": [ { "id": "lives", "name": "Lives", "description": "Lives of conjoined twins.", "findings": [ { "id": "lives-finding", "name": "Lives", "description": "Lives.", "questions": [ { "text": "How do conjoined twins who are not separated describe their lives, in their own words?", "kind": "provenance" }, { "text": "Which references are standard?", "kind": "provenance" } ] } ] }, { "id": "rights", "name": "Rights", "description": "Dignity and rights.", "findings": [ { "id": "rights-finding", "name": "Rights", "description": "Rights.", "questions": [ { "text": "What dignity and disability rights considerations apply?", "kind": "provenance" }, { "text": "Which sources are cited?", "kind": "provenance" } ] } ] } ] }, { "id": "context", "name": "Context", "description": "History and animals.", "rationale": "Context.", "layers": [ { "id": "history", "name": "History", "description": "History.", "findings": [ { "id": "history-finding", "name": "History", "description": "History.", "questions": [ { "text": "How have conjoined twins been treated historically, from the Bunker brothers to modern separations, presented with dignity?", "kind": "provenance" }, { "text": "Which entry fits the specific historical case?", "kind": "action" } ] } ] }, { "id": "animals", "name": "Animals", "description": "Conjoined animals.", "findings": [ { "id": "animals-finding", "name": "Animals", "description": "Animals.", "questions": [ { "text": "How do conjoined twinning and polycephaly occur in animals?", "kind": "provenance" }, { "text": "Which entry fits polycephaly?", "kind": "action" } ] } ] } ] } ] }, "openQuestions": [ "Should craniopagus and dicephalic parapagus be separate entries?", "How should medical and ethical sources be linked?", "The registry entry has merged aliases naming types and animal cases; should they be split off?" ], "statistics": { "bundles": 4, "layers": 8, "findings": 8, "questions": 16 } }, "draft": { "generator": "vr.draft.v3", "status": "draft-generated", "researched": false, "archetype": "abstract concept", "method": "Written from the archetype playbook - what this kind of thing needs beyond identity and provenance - and from the structure that recurred across 6,333 models already researched by two engines. Applied to this entry by rule. No source was read for this thing and no claim here is researched. This entry carries no facets of its own, so they were inferred from its domain - a guess about a whole domain applied to one thing.", "facetsInferred": true, "nextPass": "A researcher replaces this draft with a sourced specification. Treat every sentence below as a proposal to argue with.", "purpose": "Give an agent a durable, checkable way to recognise a conjoined twins, record what state it is in, and decide what may be done with it.", "whatItIs": "Let an agent explain conjoined twins and their classification respectfully and in general terms from medical sources, describe causes, care and separation decisions, relay history and notable cases with dignity, and route families to specialist centres.", "characteristics": { "substance": "abstract", "origin": "conceptual", "agency": "inert" }, "whatYouCanDoWithIt": [ "observed and measured" ], "distinguishingFeatures": [ "Names folded into this entry, which a task may need to split apart again: monozygotic conjoined twins, dizygotic conjoined twins, Ischiopagi, polycephaly, dicephalic parapagus twins, conjoined animal twins, craniopagus twins, Craniopagus parasiticus.", "8 finer distinctions are held as aliases rather than separate entries, because telling them apart needs a task that asks for it.", "Described in 55 Wikipedia languages, which is a measure of how widely the thing is known, not of how important it is." ], "openQuestionsForResearch": [ "Which of the bundles below does a real task actually need, and which are ceremony?", "What does this thing have that the facets do not capture at all?", "Which neighbouring kind is most often confused with a conjoined twins, and on what evidence are they told apart?" ], "whatItIsMadeOf": "an abstraction with no physical instance", "physicalCharacter": [ "Does nothing on its own; everything it does, something else did to it.", "These come from the domain this entry sits in rather than from the entry itself, so treat them as a first guess about the whole domain applied to one thing." ], "whatCanBeDoneWithIt": [ "observe it, measure it, record its state" ], "howItIsRecognised": [ "Nothing to see. What is recognised is an instance of it, and which instances count is exactly what is argued about." ], "relatedModels": [ { "relation": "covers", "note": "Finer kinds folded into this entry because telling them apart needs a task that asks for it. Each is a model waiting to be split out when one does.", "targets": [ "monozygotic conjoined twins", "dizygotic conjoined twins", "Ischiopagi", "polycephaly", "dicephalic parapagus twins", "conjoined animal twins", "craniopagus twins", "Craniopagus parasiticus" ] } ], "standing": "Described in 55 Wikipedia languages, which measures how widely it is written about rather than how important or how common it is. 8 finer distinctions are held inside this entry as names rather than as separate models.", "structure": { "bundles": [ { "id": "identity-and-classification", "name": "Identity, naming and classification", "description": "How an agent tells one conjoined twins from another, and a conjoined twins from things that resemble it.", "rationale": "Recognition comes before every other claim. Without stable identity nothing else in the model can be trusted to be about the same thing twice.", "layers": [ { "id": "naming-and-identifiers", "name": "Names and identifiers", "description": "The names this thing goes by and the identifiers that survive translation and time.", "findings": [ { "id": "preferred-name-and-aliases", "name": "Preferred name, aliases and local names", "description": "Which name to use, which names mean the same thing, and which merely sound similar.", "questions": [ { "id": "preferred-name-and-aliases-q01", "text": "What identifies and describes the name of a conjoined twins, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "preferred-name-and-aliases-q02", "text": "Who or what asserted this about the name of a conjoined twins, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "preferred-name-and-aliases-q03", "text": "What may an agent decide or do once the name of a conjoined twins is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] }, { "id": "stable-identifiers", "name": "Stable identifiers and external keys", "description": "Identifiers that keep pointing at this kind of thing across systems and languages.", "questions": [ { "id": "stable-identifiers-q01", "text": "What identifies and describes an identifier for a conjoined twins, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "stable-identifiers-q02", "text": "Who or what asserted this about an identifier for a conjoined twins, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "stable-identifiers-q03", "text": "What may an agent decide or do once an identifier for a conjoined twins is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "classification-and-granularity", "name": "Classification and granularity", "description": "Where a conjoined twins sits among kinds, and how finely a task needs to cut it.", "findings": [ { "id": "kind-and-parents", "name": "Kind, parents and neighbouring kinds", "description": "The classes this thing belongs to and the ones it is next to.", "questions": [ { "id": "kind-and-parents-q01", "text": "What identifies and describes the kind of a conjoined twins, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "kind-and-parents-q02", "text": "Who or what asserted this about the kind of a conjoined twins, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "kind-and-parents-q03", "text": "What may an agent decide or do once the kind of a conjoined twins is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] }, { "id": "distinguishing-features", "name": "Distinguishing features", "description": "What separates a conjoined twins from the things most often confused with it.", "questions": [ { "id": "distinguishing-features-q01", "text": "What identifies and describes what distinguishes a conjoined twins, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "distinguishing-features-q02", "text": "Who or what asserted this about what distinguishes a conjoined twins, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "distinguishing-features-q03", "text": "What may an agent decide or do once what distinguishes a conjoined twins is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] }, { "id": "state-and-lifecycle", "name": "State and lifecycle", "description": "The states a conjoined twins passes through and the events that move it between them.", "rationale": "Most decisions about a thing depend on what state it is in now, which is a claim with a time on it, not a property.", "layers": [ { "id": "lifecycle-stages", "name": "Lifecycle stages", "description": "From coming into existence to ceasing to be one of these.", "findings": [ { "id": "stages-and-transitions", "name": "Stages and transitions", "description": "The stages worth naming and what moves a conjoined twins between them.", "questions": [ { "id": "stages-and-transitions-q01", "text": "What identifies and describes the lifecycle of a conjoined twins, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "stages-and-transitions-q02", "text": "Who or what asserted this about the lifecycle of a conjoined twins, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "stages-and-transitions-q03", "text": "What may an agent decide or do once the lifecycle of a conjoined twins is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "observations-and-status", "name": "Observations and current status", "description": "What is observed about a conjoined twins, how often and by whom.", "findings": [ { "id": "observation-record", "name": "Observation record", "description": "How an observation of a conjoined twins is recorded so that it can be superseded rather than overwritten.", "questions": [ { "id": "observation-record-q01", "text": "What identifies and describes an observation of a conjoined twins, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "observation-record-q02", "text": "Who or what asserted this about an observation of a conjoined twins, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "observation-record-q03", "text": "What may an agent decide or do once an observation of a conjoined twins is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] }, { "id": "definitions-in-contest", "name": "Definitions and who holds them", "description": "What conjoined twins is taken to mean, and by whom.", "rationale": "When a field disagrees about a concept, the disagreement is the content. A model that picks one definition silently destroys the information.", "layers": [ { "id": "competing-definitions", "name": "Competing definitions", "description": "The main readings and the traditions behind them.", "findings": [ { "id": "definition-map", "name": "Definitions and their holders", "description": "Each definition with the school or body that holds it.", "questions": [ { "id": "definition-map-q01", "text": "Which definitions of conjoined twins are in use, and which tradition or body holds each?", "kind": "definition" }, { "id": "definition-map-q02", "text": "What turns on the difference between them in practice?", "kind": "boundary" } ] } ] }, { "id": "operationalisation", "name": "Operationalisation", "description": "How it is measured or applied when it has to be.", "findings": [ { "id": "operational-record", "name": "Measures and proxies", "description": "Instruments and indicators used to stand in for it.", "questions": [ { "id": "operational-record-q01", "text": "How is conjoined twins operationalised or measured in practice, and by what instrument?", "kind": "measurement" }, { "id": "operational-record-q02", "text": "What does that operationalisation leave out, and when does that matter?", "kind": "boundary" } ] } ] } ] }, { "id": "instances-and-use", "name": "Instances, use and consequence", "description": "What counts as an instance of conjoined twins and what follows from calling something that.", "rationale": "Applying a concept is an act with consequences, so a model must say what the label licenses and what it does not.", "layers": [ { "id": "instances", "name": "What counts as an instance", "description": "Clear cases, borderline cases and non-cases.", "findings": [ { "id": "instance-tests", "name": "Tests for an instance", "description": "What would settle whether something falls under it.", "questions": [ { "id": "instance-tests-q01", "text": "What would settle whether something is an instance of conjoined twins?", "kind": "boundary" }, { "id": "instance-tests-q02", "text": "Which borderline cases are argued about, and on what grounds?", "kind": "definition" } ] } ] }, { "id": "consequence", "name": "Consequence of application", "description": "Rights, duties or decisions that follow from the label.", "findings": [ { "id": "consequence-record", "name": "What the label licenses", "description": "What an agent may do once something is classified this way.", "questions": [ { "id": "consequence-record-q01", "text": "What follows practically once something is treated as conjoined twins?", "kind": "action" }, { "id": "consequence-record-q02", "text": "What must an agent not infer from the label alone?", "kind": "action" } ] } ] } ] }, { "id": "provenance-and-evidence", "name": "Provenance, evidence and time", "description": "Where every claim about a conjoined twins came from and when it held.", "rationale": "A claim without a source and a time cannot be superseded, only overwritten, and an agent that overwrites loses the ability to explain itself.", "layers": [ { "id": "source-and-authority", "name": "Source and authority", "description": "Who said it, on what evidence, and how strongly.", "findings": [ { "id": "claim-provenance", "name": "Claim provenance and confidence", "description": "The authority behind each claim about a conjoined twins and how confident it is.", "questions": [ { "id": "claim-provenance-q01", "text": "What identifies and describes a claim about a conjoined twins, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "claim-provenance-q02", "text": "Who or what asserted this about a claim about a conjoined twins, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "claim-provenance-q03", "text": "What may an agent decide or do once a claim about a conjoined twins is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] }, { "id": "time-and-versions", "name": "Time, versions and supersession", "description": "When a claim was true, when it was learnt, and what replaced it.", "findings": [ { "id": "validity-and-supersession", "name": "Validity period and supersession", "description": "How an old claim about a conjoined twins is retired without being erased.", "questions": [ { "id": "validity-and-supersession-q01", "text": "What identifies and describes the validity of a claim about a conjoined twins, and in what units or vocabulary?", "kind": "definition", "answer_data": [ "identifiers", "types and classes", "values with units", "explicit unknowns" ] }, { "id": "validity-and-supersession-q02", "text": "Who or what asserted this about the validity of a claim about a conjoined twins, by which method, and when was it true?", "kind": "provenance", "answer_data": [ "authority", "method", "evidence", "event time", "knowledge time" ] }, { "id": "validity-and-supersession-q03", "text": "What may an agent decide or do once the validity of a claim about a conjoined twins is known, and what must it refuse?", "kind": "action", "answer_data": [ "permitted actions", "preconditions", "refusals", "escalation" ] } ] } ] } ] } ] }, "statistics": { "bundles": 5, "layers": 10, "findings": 12, "questions": 32 } } } }