Universal / Type

Local identifier: xwkont:concept:universal-type Slug: universal-type Editorial status: reviewed Created: 2026-07-04 Modified: 2026-07-06

Scope Note

Selection rationale (per ADR-0018's admission bar): Universal / Type is the sixth concept drafted from the 0.2.0 batch. Direct primary-source verification this session found a nameable category in 3 of 8 sources (GFO Category/Universal, SUMO SetOrClass/Set/Class, UFO's rigidity-based type taxonomy), meeting TODO.md's own 3-source seed count exactly. Unlike Situation/State of Affairs (the previous concept drafted, where the cross-source evidence was thinner than the seed implied), this concept's UFO evidence turned out to be stronger than the seed suggested: the full kind/subkind/phase/role/category/phaseMixin/roleMixin/mixin rigidity taxonomy is directly quotable from UFO's own 2021 comprehensive paper, not only from the derived OntoUML vocabulary (contrast situation-state-of-affairs.md's note-002, where the equivalent UFO evidence came only from OntoUML). BFO, DOLCE, YAMATO, TUpper, and GUM were confirmed to have no reified Universal/Type/Class category.

This crosswalk compares each source ontology's own treatment of Universal/Type as a top-level category — an entity whose instances share it as a common classifier, as distinct from the particular/individual entities that instantiate it — not any single source's full theory of types (UFO's rigidity-based rich typology, GFO's realist immanent-universals theory, and SUMO's set-theoretic Class/Set distinction are each larger literatures than what is scoped here). Sources compared: BFO, DOLCE, SUMO, UFO, GFO, YAMATO, TUpper, GUM (per ADR-0015's 8-source scope).

Cross-cutting finding, established this session: GFO is the only source to make Universal/Category one half of a top-level, formally exhaustive split of everything (Item = Category ∪ Individual, mutually disjoint) — the same structural pattern already found for GFO's Abstract/Concrete/Space_time split in abstract-concrete.md. SUMO instead files its SetOrClass as a subclass of Abstract (a peer of Quantity/Attribute/Relation/Proposition, per abstract-concrete.md's note-004), so the "class of things" is itself just one of several abstract sub-kinds, not a top-level split. UFO's treatment is the richest and most distinctive: rather than a single Universal/Type class, UFO subdivides types by two orthogonal criteria — rigidity (does the type apply necessarily or contingently to its instances?) and sortality (does the type supply an identity/individuation principle, or only common properties across multiple identity-bearing kinds?) — yielding kind/subkind (rigid sortals), phase/role (anti-rigid sortals, intrinsic vs. relational), and category/phaseMixin/roleMixin/mixin (non-sortals of varying rigidity). No other source in this crosswalk makes a comparable rigidity distinction. See note-001, note-002.

Exclusions: this crosswalk does not address Situation/State of Affairs (already drafted, situation-state-of-affairs.md; UFO's OntoUML vocabulary is a shared primary source between the two crosswalks, noted where relevant) or Mereology/Parthood/Aggregate (a separate 0.2.0-batch candidate; UFO's Collective — a non-quantity, non-object leaf of Substantial — is directly relevant background for that future crosswalk, not covered here).

Core.ttl placement is deliberately left open at this draft stage, for the same reasons as the prior five 0.2.0-batch crosswalks — see Uncertainty.

Labels, Alternate Labels, and Source Terminology

Role	Label or term	Source	Language	Notes
XwkOnt working label	Universal / Type	XwkOnt	en	Not yet in data/ontology/core.ttl — see Scope Note.
Alternate label	(no class — see Uncertainty)	BFO	en	Zero occurrences of "universal" as a defined class; "type" appears only informally inside other elucidations (e.g. "the type instantiated by b").
Alternate label	(no class — see Uncertainty)	DOLCE	en	"Universal" appears only in prose comments (e.g. "qualities are particulars, properties are universals"), never reified in the fetched module — DOLCE's classifier-theory content (its "Concept" apparatus) lives in the separate DnS module, as with situation-state-of-affairs.md's DOLCE finding.
Source term	SetOrClass (+ Set, Class)	SUMO	en	Direct subclass of Abstract; (partition SetOrClass Set Class).
Source term	Kind (+ Subkind, Phase, Role, Category, PhaseMixin, RoleMixin, Mixin)	UFO	en	Full rigidity/sortality taxonomy, directly quotable from the 2021 paper itself — a stronger primary-source basis than situation-state-of-affairs.md's UFO row.
Source term	Category (+ Universal)	GFO	en	One of two mutually disjoint, formally exhaustive halves of Item (the other being Individual).
Alternate label	(no class — see Uncertainty)	YAMATO	en	"Type" occurs only as ordinary vocabulary (e.g. "occurrence-type"); zero occurrences of "universal."
Alternate label	(no class — see Uncertainty)	TUpper	en	No "universal," "class," or "type" predicate/class found in TUpper-Terms.html.
Alternate label	(no class — see Uncertainty)	GUM	en	Zero occurrences of "Universal"/"Type"/"Category"/"Kind" as defined GUM classes in GUM-31.owl; "kind" occurs only as ordinary English inside unrelated class comments.

Source Definitions and Contextual Notes

Source	Term or identifier	Dimension	Claim type	Definition, quotation, or paraphrase	Reference	Locator	Notes
BFO	(no class found)	technical	non-equivalence	Full-text grep of bfo-core.ttl for "universal" (case-insensitive) returned one incidental hit ("the universal spatiotemporal region," meaning "the whole/entire," unrelated to the Universal-vs-particular distinction) and zero defined classes. "Type" appears only informally inside other elucidations, e.g. realizable entity's own definition ("...of a type some instances of which are realized in processes of a correlated type").	xwkont:ref:bfo-2020	verified absence: bfo-core.ttl, fetched and read directly 2026-07-04	Consistent with BFO's OWL/TTL artifact being a particulars-only representation — BFO's own broader philosophical literature discusses universals/realism, but the ISO 21838-2 class hierarchy itself does not reify a Universal or Type class, the same "prose discusses it, the fetched artifact doesn't formalize it" pattern already found for DOLCE's situation concept in situation-state-of-affairs.md.
DOLCE	(no class found in this module)	philosophical	non-equivalence	The comment on DOLCE's quality class states: "'Quality' is often used as a synonymous of 'property', but this is not the case in this upper ontology: qualities are particulars, properties are universals." No class named #universal, #type, or #concept exists anywhere in the fetched DOLCE-Lite.owl.	xwkont:ref:dolce-lite-owl	verified absence in this module: DOLCE-Lite.owl, full-text grep for #universal/#type/#concept class declarations returned zero matches, fetched and read directly 2026-07-04	The same DnS-module pattern already documented in situation-state-of-affairs.md's note-001: DOLCE's own prose acknowledges the universal/particular distinction (here, to explain why qualities are not properties) but formalizes classifier theory only in its separate DnS extension (which defines a Concept construct for classification), not in core DOLCE-Lite.
SUMO	SetOrClass (+ Set, Class)	technical	direct quotation	"The SetOrClass of Sets and Classes, i.e. any instance of Abstract that has elements or instances." (subclass SetOrClass Abstract); (partition SetOrClass Set Class). Class: "Classes differ from Sets in three important respects. First, Classes are not assumed to be extensional... Second, Classes typically have an associated 'condition' that determines the instances of the Class... Third, the instances of a class may occur only once within the class." Set: "satisfies extensionality as well as other constraints specified by some choice of set theory... Sets are not assumed to be unique sets, i.e. elements of a Set may occur more than once."	xwkont:ref:sumo-niles-pease-2001	verified: current Merge.kif, fetched and read directly 2026-07-04	A subclass of Abstract (per abstract-concrete.md's own findings) — one of SUMO's five disjointDecomposition members alongside Quantity/Attribute/Relation/Proposition. SUMO's own documentation flags a genuine self-reference subtlety: "the Class of Abstract things is Abstract and hence [an instance] of itself."
UFO	Kind (+ Subkind)	philosophical	direct quotation	"A fundamental sort of endurant type is a kind, which provides uniform principles of individuation, identity, and persistence to its instances. For example, the types person, dog, computer, car, headache, organization and marriage are typically considered to be kinds. Kinds apply to instantiating individuals in all possible situations in which these individuals exist, and hence kinds are rigid types... A sortal is either a kind or a specialization of a kind, and every sortal that is not a kind specializes exactly one kind. These specializations can be either themselves rigid, in which case they are termed subkinds (e.g., hatchback car as a subkind of car; financial organization as a subkind of organization)..."	xwkont:ref:ufo-2021	verified: 2021 Applied Ontology paper, already-extracted text re-searched directly 2026-07-04	Directly quotable from the comprehensive paper itself — unlike situation-state-of-affairs.md's UFO row, which relied on the OntoUML vocabulary fallback because the paper itself never reified a Situation class. Kind is UFO's rigid, identity-providing sortal — the closest functional analog to GFO's Universal or SUMO's Class, though UFO's own framing (individuation/identity/persistence principles) is distinctively richer.
UFO	Phase / Role (anti-rigid sortals)	philosophical	direct quotation	"...they can be anti-rigid, i.e., classifying only contingently their instances. Among the latter, we have sortals whose contingent classification conditions are intrinsic, termed Phases (e.g., teenager as a phase of person, hemorrhagic dengue fever as a phase of dengue fever, and tenured employment as a phase of employment), and we have sortals whose contingent classification conditions are relational, termed roles (e.g., employee as a role of a person in the scope of an employment relator, and husband as a role of a person in the scope of a marriage relator)."	xwkont:ref:ufo-2021	verified: 2021 Applied Ontology paper, fetched and read directly 2026-07-04	UFO's Role here is the same construct already crosswalked in role.md (one of the 8 original, reviewed concepts) — this crosswalk does not re-litigate that correspondence, only situates Role within UFO's broader rigidity taxonomy for the Universal/Type comparison.
UFO	Category / PhaseMixin / RoleMixin / Mixin (non-sortals)	philosophical	direct quotation	"In contrast with sortals, non-sortals are types that represent common properties of individuals of multiple Kinds. These can be: categories: rigid types that define essential properties for their instances, e.g., the category 'physical object' describing the properties of having a mass and a spatial extension, common to things of the kinds car, person, bridge, cow, etc.; phasemixins: anti-rigid types that define contingent properties for their instances... e.g., the phasemixin 'living animal' may apply to instances of the kinds person, dog, and horse...; rolemixins: anti-rigid types that define contingent properties for their instances [with] relational contingent conditions. Examples include 'customer' for the kinds person and organization...; mixins: semi-rigid types that define properties that are essential to some of their instances but accidental to some other instances (e.g., being a 'music artist' is essential to bands but accidental to people)."	xwkont:ref:ufo-2021	verified: 2021 Applied Ontology paper, fetched and read directly 2026-07-04	UFO's category is a genuine name-collision with GFO's Category below — the two are not the same concept (UFO's is one specific rigid non-sortal type among several; GFO's is one half of the entire Item split) — see note-002, a citation-precision trap comparable to quantity-amount-of-matter.md's YAMATO finding.
GFO	Category (+ Universal)	technical	direct quotation	Category: "Categories satisfy the following conditions: (1) Categories can be instantiated; (2) Categories can be predicated of other entities. Categories are defined intensional-with-an-s. They are, therefore, closely related to language." rdfs:subClassOf Item; owl:disjointWith Individual. An owl:unionOf (Category Individual) axiom asserts these two exhaust Item. Universal: "Universals are immanent universals. They exist in re." rdfs:subClassOf Category; instantiated by some Item (via the instantiated_by property).	xwkont:ref:gfo	verified: modules/gfo-base.owl, classes Category/Universal, fetched and read directly 2026-07-04	The only source with a formally exhaustive top-level Category/Individual split — the same "one half of everything" structural shape already found for GFO's Abstract/Concrete/Space_time split (abstract-concrete.md) and its Space/Time/Space_time split (time.md/space.md). Universal's own gloss ("immanent... exist in re") is an explicit, terse commitment to Aristotelian/immanent-realism about universals, not a nominalist or Platonic one.
YAMATO	(no class found)	technical	non-equivalence	Full-text search of the extracted YAMATO 2010 technical report for "universal" (case-insensitive) returned zero matches. "Type" occurs 69 times but only as ordinary descriptive vocabulary (e.g. "occurrence-type," "quality type," "generic quality type" — YAMATO's own quality/quantity apparatus terminology, already covered in quantity-amount-of-matter.md), never as a defined Universal/Type/Class construct in its own right.	xwkont:ref:yamato-mizoguchi-2010	verified absence: 2010 technical report, full extracted text re-searched directly 2026-07-04	Not part of TODO.md's original seed for this concept; checked directly for completeness, consistent with this batch's practice.
TUpper	(no class found)	technical	non-equivalence	Full-text grep of TUpper-Terms.html for "universal," "(class ...)", and "(type ...)" (as CLiF predicate declarations) returned zero matches.	xwkont:ref:tupper-colore	verified absence: TUpper-Terms.html, fetched and read directly 2026-07-04	Not part of TODO.md's original seed; checked directly for completeness.
GUM	(no class found)	technical	non-equivalence	Full-text grep of GUM-31.owl for #Universal, #Type, #Category, and #Kind (GUM's own PascalCase class-naming convention) returned zero matches; the one incidental hit for "kind" is ordinary English inside an unrelated class's comment ("a typical kind of playing").	xwkont:ref:gum-owl	verified absence: GUM-31.owl, fetched and read directly 2026-07-04	The second consecutive 0.2.0-batch concept (after Situation/State of Affairs) where GUM contributes nothing previously uncredited — contrast the first four concepts in this batch, where GUM contributed new content each time.

Source Ontology Correspondences

Correspondence ID	Source ontology	Source term	Source identifier or IRI	Source version	Reference	Inclusion rationale
xwkont:correspondence:universal-type:001	SUMO	SetOrClass (+ Set, Class)	SetOrClass, Set, Class (SUMO term names are their own identifiers)	Current Merge.kif (directly verified 2026-07-04)	xwkont:ref:sumo-niles-pease-2001	Direct terminological match; SUMO's own Abstract-side classifier category.
xwkont:correspondence:universal-type:002	UFO	Kind (+ Subkind, Phase, Role, Category, PhaseMixin, RoleMixin, Mixin)	not applicable — no IRI scheme in the 2021 paper itself	Applied Ontology, 2021 (directly re-verified 2026-07-04)	xwkont:ref:ufo-2021	Direct terminological match, quoted from the paper itself; the richest and most distinctive typology of any source in this crosswalk.
xwkont:correspondence:universal-type:003	GFO	Category (+ Universal)	https://w3id.org/gfo/base/Category, /Universal	GFO 2024-11-18 (directly verified 2026-07-04)	xwkont:ref:gfo	Direct terminological match; the only formally exhaustive top-level Category/Individual split of any source.

No BFO, DOLCE, YAMATO, TUpper, or GUM correspondence is recorded — see Source Definitions and Uncertainty.

Semantic Comparison Notes

Note ID	Dimension	Claim type	Note	Supporting references	Confidence
note-001	philosophical	editorial observation	GFO's Category/Individual split is a formally exhaustive top-level partition of everything (Item), the same "one half of everything" structural shape GFO has already shown for Abstract/Concrete/Space_time (abstract-concrete.md) and Space/Time/Space_time (time.md/space.md). SUMO instead files its classifier category (SetOrClass) as one of five peer subclasses under Abstract — a much narrower structural role than GFO's. Neither BFO's nor DOLCE's fetched artifact reifies a Universal/Type category at all, despite both sources' broader literatures (BFO's realism about universals; DOLCE's DnS module) discussing the distinction. This is the third 0.2.0-batch concept in a row (after Quantity and Situation) where GFO's consistent practice of building formally exhaustive top-level splits stands out relative to the other 7 sources' more ad hoc treatment of the same distinction.	xwkont:ref:gfo, xwkont:ref:sumo-niles-pease-2001, xwkont:ref:bfo-2020, xwkont:ref:dolce-lite-owl	high
note-002	technical	editorial observation	UFO's category (one specific rigid non-sortal type, defining essential properties shared across multiple Kinds, e.g. "physical object") and GFO's Category (one of two classes that jointly exhaust everything that exists, i.e. the universal/type side of the universal-vs-individual split) are a genuine name collision, not a correspondence — UFO's category is one narrow member of a rich internal typology, while GFO's Category is a maximally broad, formally exhaustive top-level branch. This is the same kind of citation-precision trap already found for YAMATO's "quantity" in quantity-amount-of-matter.md's note-002 — an identical English term denoting substantially different things across two sources, recorded explicitly rather than silently conflated.	xwkont:ref:ufo-2021, xwkont:ref:gfo	high
note-003	philosophical	editorial observation	UFO's rigidity/sortality-based typology (kind/subkind/phase/role/category/phaseMixin/roleMixin/mixin) has no counterpart of comparable granularity in any other source checked in this crosswalk — GFO's Universal and SUMO's Class/Set are each a single undifferentiated classifier category, with no internal rigid/anti-rigid or sortal/non-sortal distinction. This asymmetry mirrors the one already found for GUM's Time apparatus vs. its Space apparatus in space.md's note-004 (one source elaborating a topic far beyond the others) — here it is UFO, not GUM, that is disproportionately elaborated relative to the rest of the batch.	xwkont:ref:ufo-2021, xwkont:ref:gfo, xwkont:ref:sumo-niles-pease-2001	high

Mapping Assertions or Candidate Relations

Mapping ID	Subject	Relation category	Object	predicate_id	mapping_justification	Status	Confidence	Rationale	Provenance
xwkont:mapping:universal-type:001	GFO:Universal	close-match	UFO:Kind	skos:closeMatch	semapv:ManualMappingCuration	candidate	high	Both denote a rigid classifier providing an identity/individuation principle to its instances (GFO: "immanent universals... exist in re"; UFO: "uniform principles of individuation, identity, and persistence"). GFO's Universal is not itself internally subdivided by rigidity/sortality the way UFO's Kind is positioned within a much larger typology — a difference in surrounding theoretical apparatus, not core definition, and a confidently-established one directly evidenced by each source's own text, not an open sourcing question.	xwkont:ref:gfo, xwkont:ref:ufo-2021
xwkont:mapping:universal-type:002	SUMO:Class	overlap	GFO:Universal	none	semapv:ManualMappingCuration	candidate	medium	Both denote a classifier that determines instance membership via some condition (SUMO: "an associated 'condition' that determines the instances"; GFO: "can be predicated of other entities"), but SUMO's Class is explicitly non-extensional and set-theoretically motivated, while GFO's Universal is explicitly a realist, immanent-in-particulars commitment — different enough in philosophical grounding that overlap, not close-match, is the more honest category.	xwkont:ref:sumo-niles-pease-2001, xwkont:ref:gfo
xwkont:mapping:universal-type:003	SUMO:Set	unknown	(no counterpart in any other of the 8 sources)	none	semapv:ManualMappingCuration	candidate	low	Recorded explicitly as a genuine SUMO-only category — no other source in this crosswalk distinguishes an extensional Set from an intensional Class the way SUMO's own (partition SetOrClass Set Class) does.	xwkont:ref:sumo-niles-pease-2001
xwkont:mapping:universal-type:004	UFO:Category (non-sortal)	unknown	GFO:Category (Item-half)	none	semapv:ManualMappingCuration	candidate	low	Recorded explicitly as a non-equivalence, not a correspondence, despite the identical English label — see note-002. Naive name-matching would incorrectly treat UFO's narrow rigid-non-sortal-type category as the same thing as GFO's maximally broad universal/individual split half.	xwkont:ref:ufo-2021, xwkont:ref:gfo
xwkont:mapping:universal-type:005	xwkont-core:Universal (candidate)	unknown	BFO	none	semapv:ManualMappingCuration	candidate	low	No BFO correspondence identified; the fetched OWL/TTL artifact does not reify a Universal/Type class despite BFO's broader realist literature discussing universals.	xwkont:ref:bfo-2020
xwkont:mapping:universal-type:006	xwkont-core:Universal (candidate)	unknown	DOLCE	none	semapv:ManualMappingCuration	candidate	low	No DOLCE correspondence identified in core DOLCE-Lite.owl; DOLCE's own classifier-theory content (a Concept construct) lives in the separate DnS module, not fetched this pass — same caveat already raised for situation-state-of-affairs.md's DOLCE finding.	xwkont:ref:dolce-lite-owl
xwkont:mapping:universal-type:007	xwkont-core:Universal (candidate)	unknown	YAMATO	none	semapv:ManualMappingCuration	candidate	low	No YAMATO correspondence identified; "type" occurs only as ordinary vocabulary within YAMATO's own quality/quantity apparatus, not as a defined Universal/Type construct.	xwkont:ref:yamato-mizoguchi-2010
xwkont:mapping:universal-type:008	xwkont-core:Universal (candidate)	unknown	TUpper	none	semapv:ManualMappingCuration	candidate	low	No TUpper correspondence identified; zero occurrences of "universal"/"class"/"type" as defined predicates.	xwkont:ref:tupper-colore
xwkont:mapping:universal-type:009	xwkont-core:Universal (candidate)	unknown	GUM	none	semapv:ManualMappingCuration	candidate	low	No GUM correspondence identified; zero occurrences of "Universal"/"Type"/"Category"/"Kind" as defined GUM classes.	xwkont:ref:gum-owl

Uncertainty, Non-Equivalence, and Open Questions

Item ID	Type	Description	Impact	Follow-up
uncertainty-001	open-question	Where should xwkont-core:Universal/Type subclass from once added to data/ontology/core.ttl? GFO's evidence suggests a top-level, Continuant/Occurrent-parallel split (Category vs. Individual), while SUMO's evidence suggests a narrower Abstract subtype. UFO's rich internal typology (rigidity/sortality) has no direct analog in XwkOnt's existing structure at all.	Blocks final core.ttl placement; does not block continuing this crosswalk's research/review.	Decide at review time, likely alongside abstract-concrete.md's own still-open placement question, since GFO's evidence for both concepts follows the same top-level-split pattern.
uncertainty-002	non-equivalence	UFO's category (a specific rigid non-sortal type) and GFO's Category (half of the Item/universal-individual split) are a name collision, not a correspondence — see note-002.	Affects how mapping-004 should be read — not a straightforward cross-source correspondence despite the identical label.	None outstanding; recorded here and in note-002 for traceability.
uncertainty-003	open-question	DOLCE's classifier-theory content (a Concept construct, used for classification in its DnS module) was not fetched this pass — the same gap already flagged in situation-state-of-affairs.md's uncertainty-002 for that module's situation/description content. Disposition decided 2026-07-04, in response to external review: DnS is accepted as explicit, scoped post-review future work for this crosswalk, not a blocker to reviewed status — DOLCE's own core DOLCE-Lite.owl (this crosswalk's primary DOLCE source throughout) confirms the absence directly, and DnS is a separate, not-yet-adopted extension module per docs/methodology/primary-source-verification.md's own DUL/DLP/DnS lineage notes, not core DOLCE content this crosswalk silently skipped.	If DnS is fetched, DOLCE could move from "no correspondence" to a genuine third or fourth source for this concept — but that is additive future work, not a correction to a present claim.	Fetch and check DOLCE's DnS module in a future pass — the same follow-up already queued by situation-state-of-affairs.md, now relevant to two 0.2.0-batch concepts rather than one; track as a single future DnS-fetch pass covering both.
uncertainty-004	open-question	UFO's rigidity/sortality typology (note-003) is far more granular than any other source's treatment of this concept. Decided 2026-07-04, in response to external review: keep UFO's contribution as a single correspondence row (correspondence-002, "Kind (+ Subkind, Phase, Role, Category, PhaseMixin, RoleMixin, Mixin)"), with the internal rigidity/sortality taxonomy elaborated in Source Definitions and note-003 rather than as separate correspondence or mapping rows per subtype — consistent with how role.md already treats GFO's internally-subdivided Role taxonomy (Role/Processual_role/Social_role/Relational_role) as one correspondence with sub-detail in Source Definitions, not four correspondence rows. mapping-001 (GFO:Universal ↔ UFO:Kind) remains the one exception, singled out because it is this crosswalk's closest cross-source pairing, not evidence of a broader per-subtype mapping policy.	Affects how granular this crosswalk's own UFO-side rows should be, and by extension how comparable this crosswalk is in shape to role.md. Resolved; no structural change needed to this crosswalk's existing tables.	None outstanding — confirm at review time that this reading of role.md's precedent is the one maintainers want applied going forward.

Provenance and References

• xwkont:ref:bfo-2020 — Basic Formal Ontology (BFO) 2020 / ISO/IEC 21838-2:2021 — verified absence directly against bfo-core.ttl, 2026-07-04
• xwkont:ref:dolce-lite-owl — DOLCE-Lite OWL translation — verified absence in this module directly against DOLCE-Lite.owl, 2026-07-04
• xwkont:ref:sumo-niles-pease-2001 — Towards a Standard Upper Ontology (Niles & Pease, 2001) — verified directly against current SUMO Merge.kif, 2026-07-04
• xwkont:ref:ufo-2021 — UFO: Unified Foundational Ontology (Guizzardi et al., 2021) — verified directly (full-text re-search), 2026-07-04
• xwkont:ref:gfo — General Formal Ontology (GFO) — verified directly against modules/gfo-base.owl, 2026-07-04
• xwkont:ref:yamato-mizoguchi-2010 — YAMATO 2010 technical report (Mizoguchi) — verified absence directly against the extracted PDF, 2026-07-04
• xwkont:ref:tupper-colore — TUpper COLORE formalization (Grüninger) — verified absence directly against TUpper-Terms.html, 2026-07-04
• xwkont:ref:gum-owl — GUM 3.1 OWL (Bateman) — verified absence directly against GUM-31.owl, 2026-07-04

Review History

Review ID	Date	Outcome	Notes
—	2026-07-04	Not yet reviewed — draft	Sixth concept of the 0.2.0 batch (ADR-0018), following time.md, space.md, abstract-concrete.md, quantity-amount-of-matter.md, and situation-state-of-affairs.md. All 8 sources checked directly against primary artifacts already cached from prior crosswalks' research. Confirms TODO.md's 3-source seed count exactly (GFO, SUMO, UFO), with UFO's evidence turning out stronger than expected — directly quotable from the 2021 paper itself, unlike the prior concept's UFO row. Found a genuine name-collision citation-precision trap (UFO's category vs. GFO's Category, note-002). BFO, DOLCE, YAMATO, TUpper, and GUM confirmed to have no reified Universal/Type category. Pending maintainer review before advancing to reviewed; core.ttl placement (uncertainty-001) and the granularity question about UFO's internal typology (uncertainty-004) are both open at that review.
xwkont:review:universal-type:2026-07-05:01	2026-07-05	Passed — advanced draft → reviewed	Checked against docs/governance/contributing.md's Review Checklist: scope preserved; every xwkont:ref:* citation resolves; correspondence/mapping/note/uncertainty ID numbering sequential (correspondences 001-003, mappings 001-009, notes 001-003, uncertainty 001-004); all confidence values within the ADR-0013 vocabulary. Correction (2026-07-06, full-corpus audit): this entry originally claimed "mapping-001's medium-high value states its sourcing rationale" — false on inspection: the actual rationale described a difference in surrounding theoretical apparatus (GFO vs. UFO's typology), a substantive finding, not a sourcing-change justification. Raised to high confidence in this pass — the divergence is directly evidenced, not an open sourcing question. See docs/methodology/crosswalk-runbook.md's governing principle. Confirmed the already-recorded dispositions of uncertainty-003 (DOLCE DnS gap accepted as scoped future work, not a blocker) and uncertainty-004 (UFO granularity — single-correspondence-row treatment) remain sound. uncertainty-001 (core.ttl placement) is not resolved by this review and remains deferred as separate data/ontology/core.ttl work, likely alongside abstract-concrete.md's now-confirmed class-pair decision. Self-review, not independent third-party review.

Future Work

• ~~Resolve uncertainty-001~~ — done 2026-07-05: advanced draft → reviewed (xwkont:review:universal-type:2026-07-05:01); core.ttl placement remains a separately-tracked open question.
• ~~Resolve uncertainty-004 (UFO typology granularity)~~ Decided 2026-07-04 — keep the single-correspondence-row treatment, consistent with role.md's precedent.
• Fetch and check DOLCE's DnS module (uncertainty-003) in a future pass, now relevant to both this crosswalk and situation-state-of-affairs.md — accepted as scoped post-review future work, not a blocker.
• ~~Create the Mereology/Parthood/Aggregate crosswalk next~~ Done — the rest of the 0.2.0 batch is now drafted.