Change

Local identifier: xwkont:concept:change Slug: change Editorial status: reviewed Created: 2026-07-07 Modified: 2026-07-07

Scope Note

This candidate is about a source ontology's own change apparatus, meaning change as a reified class or explicit family of classes, not about:

• the instantaneous-reading case of GFO Change already handled in docs/crosswalks/concepts/event.md (event:006 / event:007);
• GFO Process versus Change disjointness already handled in docs/crosswalks/concepts/process.md;
• ordinary prose uses of change, alter, transform, or modify inside unrelated class glosses.

Direct verification leaves two positive sources, not one: GFO and SUMO. In GFO, the remaining uncrosswalked thread after event.md is the extended-process reading of Change, surfaced as Continuous_change and its deprecated equivalent Intrinsic_change, plus the source-internal deprecated pair Extrinsic_change / Instantaneous_change. In SUMO, InternalChange is a real subclass of Process with its own change family underneath it, including StateChange, QuantityChange, SurfaceChange, ShapeChange, ChemicalProcess, BiologicalProcess, and Creation.

The other six sources did not surface a dedicated change class in the artifacts checked today. DOLCE, UFO, YAMATO, TUpper, and GUM do use change language, but in the checked source text that language stays local to other class glosses or prose rather than becoming a first-class change apparatus. BFO does not reify change separately in the checked core artifact.

No source-side explicit equivalence or alternate-label assertion was found that would off-ramp this candidate into event.md or process.md. The source-side structure remains distinct enough to keep this as a standalone crosswalk.

Labels, Alternate Labels, and Source Terminology

Role	Label or term	Source	Language	Notes
XwkOnt working label	Change	XwkOnt	en	Working label for source-side change apparatuses.
Source term	Change	GFO	en	Broad source anchor; the instantaneous-reading case is already handled in event.md, so this draft keeps the extended-process reading in view.
Source term	Continuous_change	GFO	en	The surviving GFO class for the extended-reading side of Change.
Source term	Intrinsic_change	GFO	en	Obsolete/deprecated in source; explicitly paired with Continuous_change.
Source term	Extrinsic_change	GFO	en	Obsolete/deprecated in source; explicitly paired with Instantaneous_change, which event.md already covers.
Source term	InternalChange	SUMO	en	Real change-family class under Process.
Source term	StateChange	SUMO	en	Concrete InternalChange subtype for physical-state change.
Source term	(no dedicated change class found)	BFO	en	No dedicated change apparatus found in the checked BFO core artifact.
Source term	(no dedicated change class found; change language only)	DOLCE	en	Change language appears in comments and related prose, but not as a first-class Change class in the checked artifact.
Source term	(no dedicated change class found)	UFO	en	Change appears in prose about events and processes, but not as a dedicated class in the checked paper.
Source term	(no dedicated change class found)	YAMATO	en	Change language appears in prose about processes and events, not as a dedicated class.
Source term	(no dedicated change class found)	TUpper	en	No dedicated change class found in the fetched TUpper artifacts.
Source term	(no dedicated change class found)	GUM	en	Change language appears inside other class glosses, but not as a dedicated class.

Source Definitions and Contextual Notes

Source	Term or identifier	Dimension	Claim type	Definition, quotation, or paraphrase	Reference	Locator	Notes
GFO	Change	technical	editorial observation	The broad GFO Change class already has its instantaneous-reading case mapped in event.md (event:006 / event:007). This draft keeps the remaining extended-process reading in view rather than restating that already-reviewed content.	xwkont:ref:gfo	modules/gfo-base.owl, class Change, fetched and read directly 2026-07-07	Process is separately owl:disjointWith Change in the same module, a relation already recorded in process.md.
GFO	Continuous_change	technical	direct quotation	For the purpose of formalizing continuous changes, a minimal chronoid universal D(c) is employed in order to capture the idea of observable differences during certain chronoids, whereas the change itself does not allow the observation of a difference. The predicate change(e1,e2, u1, u2, u, D(c)) is intended to formalize this approach. Continuous changes occur over time (a chronoid).	xwkont:ref:gfo	modules/gfo-base.owl, class Continuous_change, fetched and read directly 2026-07-07	The source makes this a subclass of Change and explicitly pairs it with deprecated Intrinsic_change.
GFO	Intrinsic_change	technical	direct quotation	For the purpose of formalizing intrinsic changes, a minimal chronoid universal D(c) is employed in order to capture the idea of observable differences during certain chronoids, whereas the change itself does not allow the observation of a difference. The predicate change(e1,e2, u1, u2, u, D(c)) is intended to formalize this approach.	xwkont:ref:gfo	modules/gfo-base.owl, class Intrinsic_change, fetched and read directly 2026-07-07	Marked owl:deprecated true in source and owl:equivalentClass to Continuous_change. Keep as source history, not live primary terminology.
GFO	Extrinsic_change	technical	direct quotation	Extrinsic changes are represented by change(e1,e2, u1, u2, u), where e1 and e2 are a pair of coincident process boundaries, and u1 and u2 are disjoint sub-universals of u.	xwkont:ref:gfo	modules/gfo-base.owl, class Extrinsic_change, fetched and read directly 2026-07-07	Marked owl:deprecated true in source and owl:equivalentClass to Instantaneous_change; the instantaneous branch is already handled in event.md.
SUMO	InternalChange	technical	direct quotation	Processes which involve altering an internal property of an Object, e.g. the shape of the Object, its coloring, its structure, etc. Processes that are not instances of this class include changes that only affect the relationship to other objects, e.g. changes in spatial or temporal location.	xwkont:ref:sumo-niles-pease-2001	Merge.kif, class InternalChange, fetched and read directly 2026-07-07	A real subclass of Process; the source also places StateChange, QuantityChange, SurfaceChange, ShapeChange, ChemicalProcess, BiologicalProcess, and Creation under this family.
SUMO	StateChange	technical	direct quotation	Any Process where the PhysicalState of part of the patient of the Process changes.	xwkont:ref:sumo-niles-pease-2001	Merge.kif, class StateChange, fetched and read directly 2026-07-07	A concrete InternalChange subtype, useful as a witness to the family structure.
BFO	(no dedicated change class found)	technical	non-equivalence	Direct search of the checked BFO core artifact found no dedicated change class or property.	xwkont:ref:bfo-2020	bfo-core.ttl, fetched and read directly 2026-07-07	Scoped absence in the checked artifact.
DOLCE	(no dedicated change class found; change language only)	technical	non-equivalence	The checked DOLCE-Lite artifact uses change in comments and nearby prose, but does not reify a dedicated Change class in the file read for this pass.	xwkont:ref:dolce-lite-owl	DOLCE-Lite.owl, fetched and read directly 2026-07-07	Adjacent evidence only.
UFO	(no dedicated change class found)	technical	non-equivalence	The checked UFO 2021 paper uses change extensively in prose -- including two whole subsections, "4.3. Property change" and "4.4. Event change" -- but never introduces a dedicated Change class or formal definition (grep-confirmed: zero occurrences of "Change ::" or any capitalized standalone "Change" term). The subsections instead model change using UFO's existing apparatus (Quality, Situation, Kind), e.g.: "Events are past entities in UFO and cannot genuinely change. Alleged change in a perdurant is thus either a reflection of a perdurant having temporal parts with different properties, or, a change in the underlying endurant that is the focus of that event."	xwkont:ref:ufo-2021	independently re-verified 2026-07-07 (session-051) against a complete full-text extraction of the 2021 paper (the DOI-linked source returned HTTP 403 again this session, the same recurring block recorded elsewhere in this repository; the extraction reused here is the same one modality.md, non-physical-social-object.md, symbol-sign-representation.md, list-sequence.md, and continuous-discrete.md independently located and reused for their own UFO checks). Prior review flagged this row as inherited from the Codex draft, not independently re-checked; now confirmed.	Prose-only usage, confirmed by independent full-text search, not merely inherited from the draft.
YAMATO	(no dedicated change class found)	technical	non-equivalence	The checked YAMATO report has a dedicated prose subsection, "3.2.3 On change" ("in order to talk about change properly, we need a non-changing thing keeping its identity during the change process, otherwise, there cannot exist a change but just a difference"), but this motivates the following quality-role discussion rather than defining a first-class Change category -- no capitalized standalone "Change" term or formal definition found.	xwkont:ref:yamato-mizoguchi-2010	independently re-verified 2026-07-07 (session-051): YAMATO101216.pdf re-fetched fresh via the Wayback Machine snapshot and re-extracted with pdftotext. Prior review flagged this row as inherited from the Codex draft, not independently re-checked; now confirmed.	Prose-only usage, confirmed by independent full-text search, not merely inherited from the draft.
TUpper	(no dedicated change class found)	technical	non-equivalence	No dedicated change class was found in the fetched TUpper artifacts.	xwkont:ref:tupper-colore	TUpper-Terms.html, tupper.all.owl, tupper.clif, fetched and read directly 2026-07-07	Scoped absence.
GUM	(no dedicated change class found)	technical	non-equivalence	Change language appears inside other class glosses (DoingANDHappening: "It also involves change over time, such as circumstantial change, qualitative change, or change in possession (HM 1999: 132)"), but no dedicated Change class exists (grep-confirmed: no owl:Class block for a Change IRI anywhere in the file).	xwkont:ref:gum-owl	independently re-verified 2026-07-07 (session-051) against GUM-31.owl.txt, re-fetched fresh via the same Wayback Machine snapshot used elsewhere in this repository. Prior review flagged this row as inherited from the Codex draft, not independently re-checked (a same-session fetch attempt via a different archive URL had failed); now confirmed via the working snapshot URL.	Scoped absence, confirmed by independent full-text search, not merely inherited from the draft.

Source Ontology Correspondences

Correspondence ID	Source ontology	Source term	Source identifier or IRI	Source version	Reference	Inclusion rationale
xwkont:correspondence:change:001	GFO	Change / Continuous_change / Intrinsic_change / Extrinsic_change	https://w3id.org/gfo/base/Change, https://w3id.org/gfo/base/Continuous_change, https://w3id.org/gfo/base/Intrinsic_change, https://w3id.org/gfo/base/Extrinsic_change	GFO base 2024-11-18	xwkont:ref:gfo	GFO reifies change as a real source-side apparatus, but the instantaneous side is already handled in event.md. This row keeps the extended-process side and the source-internal deprecated names visible together.
xwkont:correspondence:change:002	SUMO	InternalChange / StateChange	InternalChange / StateChange	SUMO Merge.kif	xwkont:ref:sumo-niles-pease-2001	SUMO reifies a dedicated change family under Process, with StateChange as a concrete subtype.
xwkont:correspondence:change:003	BFO	(no dedicated change class found)	none	BFO 2020	xwkont:ref:bfo-2020	Scoped absence in the checked core artifact.
xwkont:correspondence:change:004	DOLCE	(no dedicated change class found; change language only)	none	DOLCE-Lite OWL	xwkont:ref:dolce-lite-owl	Scoped absence in the checked artifact.
xwkont:correspondence:change:005	UFO	(no dedicated change class found)	none	UFO 2021 paper (independently verified against a complete full-text extraction, 2026-07-07)	xwkont:ref:ufo-2021	Confirmed absence -- two dedicated prose subsections ("Property change," "Event change") discuss the phenomenon at length using existing UFO apparatus, but no dedicated Change class exists.
xwkont:correspondence:change:006	YAMATO	(no dedicated change class found)	none	YAMATO 2010 report (independently re-fetched and re-extracted, 2026-07-07)	xwkont:ref:yamato-mizoguchi-2010	Confirmed absence -- a dedicated prose subsection ("3.2.3 On change") motivates the quality-role discussion that follows, but no first-class Change category is defined.
xwkont:correspondence:change:007	TUpper	(no dedicated change class found)	none	TUpper COLORE formalization	xwkont:ref:tupper-colore	Scoped absence in the checked artifacts.
xwkont:correspondence:change:008	GUM	(no dedicated change class found)	none	GUM 3.1 OWL (independently re-fetched, 2026-07-07)	xwkont:ref:gum-owl	Confirmed absence -- DoingANDHappening's own comment describes "change over time," but no dedicated Change class exists in the file.

Semantic Comparison Notes

Note ID	Dimension	Claim type	Note	Supporting references	Confidence
note-001	technical	editorial observation	GFO's change apparatus is internally split along two source-side axes: one axis distinguishes the instantaneous reading already handled in event.md from the remaining extended-process reading, and the other axis distinguishes intrinsic from extrinsic change. The deprecated names are explicit source history, not separate conceptual territory.	xwkont:ref:gfo, docs/crosswalks/concepts/event.md	high
note-002	technical	editorial observation	SUMO's InternalChange is a real family under Process, not a prose-only gloss. Its defining criterion is internal-property alteration, which excludes changes that only alter spatial or temporal location. That makes it a genuine source-side change apparatus, but with a different organizing principle from GFO's chronoid-based split.	xwkont:ref:sumo-niles-pease-2001	high
note-003	technical	editorial observation	The other six sources remain scoped absences for this candidate. DOLCE, UFO, YAMATO, TUpper, and GUM use change language in other contexts, but none of the checked artifacts reify a dedicated change class; BFO's checked core artifact also does not.	xwkont:ref:bfo-2020, xwkont:ref:dolce-lite-owl, xwkont:ref:ufo-2021, xwkont:ref:yamato-mizoguchi-2010, xwkont:ref:tupper-colore, xwkont:ref:gum-owl	high
note-004	technical	editorial observation	This is a multi-source crosswalk, but the second source does not come from an explicit source-side equivalence assertion. It survives as a standalone scope because SUMO reifies InternalChange directly; event.md and process.md do not already settle that material.	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:change:001	GFO:Continuous_change	related	SUMO:InternalChange	none	semapv:ManualMappingCuration	candidate	low	Both are real source-side change classes, but their defining tests differ: GFO anchors continuous change in chronoids and observable differences over time, while SUMO anchors internal change in alteration of an object's internal properties. Related, but not equivalent.	xwkont:ref:gfo, xwkont:ref:sumo-niles-pease-2001

Uncertainty, Non-Equivalence, and Open Questions

Item ID	Type	Description	Impact	Follow-up
uncertainty-001	resolved	The instantaneous-reading side of GFO Change is already handled in event.md (event:006 / event:007). This draft intentionally does not restate that content.	Keeps scope on the remaining extended-process side and avoids duplication.	No action needed.
uncertainty-002	resolved	GFO explicitly pairs Continuous_change with deprecated Intrinsic_change, and Extrinsic_change with deprecated Instantaneous_change. The source also marks the latter two as owl:deprecated true.	The deprecated names remain source history, not separate live correspondences.	No action needed.
uncertainty-003	resolved	SUMO's InternalChange is a genuine subclass of Process, and the checked source file shows a larger internal-change family under it.	Confirms the candidate is not GFO-only.	No action needed.
uncertainty-004	open-question	Whether xwkont:mapping:change:001 should remain related or be tightened later if a source-side justification for a closer relation appears.	Confidence only; does not affect scope.	Leave as related unless a later source directly asserts a stronger link.
uncertainty-005	~~uncertainty~~ Resolved 2026-07-07 (session-051): UFO's, YAMATO's, and GUM's absence claims, previously carried unverified from the Codex draft, were independently re-fetched/re-extracted and full-text searched for "change." All three confirmed: UFO has two dedicated prose subsections ("Property change," "Event change") but no formal Change class; YAMATO has a dedicated prose subsection ("On change") but no first-class Change category; GUM has descriptive "change over time" language inside DoingANDHappening's comment but no dedicated Change class. The Codex draft's original claims turn out correct in substance, now independently confirmed rather than merely inherited.	UFO's, YAMATO's, and GUM's absence claims were not independently re-fetched during the prior review pass -- carried from the Codex draft's own citations, not freshly re-verified.	These three sources' absence claims were unverified, not confirmed, unlike GFO/SUMO/BFO/DOLCE/TUpper.	Resolved -- no further action needed.

Provenance and References

• xwkont:ref:gfo — General Formal Ontology (GFO) base module — verified directly against modules/gfo-base.owl, 2026-07-07; confirmed Change, Continuous_change, deprecated Intrinsic_change, deprecated Extrinsic_change, and the Process/Change disjointness
• xwkont:ref:sumo-niles-pease-2001 — SUMO Merge.kif / Niles and Pease 2001 record — verified directly against Merge.kif, 2026-07-07; confirmed InternalChange and StateChange
• xwkont:ref:bfo-2020 — BFO 2020 — verified absence of a dedicated change class directly against bfo-core.ttl, 2026-07-07
• xwkont:ref:dolce-lite-owl — DOLCE-Lite OWL translation — verified absence of a dedicated change class directly against DOLCE-Lite.owl, 2026-07-07
• xwkont:ref:ufo-2021 — UFO: Unified Foundational Ontology — verified absence of a dedicated change class directly against the 2021 paper text, 2026-07-07
• xwkont:ref:yamato-mizoguchi-2010 — YAMATO technical report — verified absence of a dedicated change class directly against the report, 2026-07-07
• xwkont:ref:tupper-colore — TUpper COLORE formalization — verified absence of a dedicated change class directly against the fetched TUpper artifacts, 2026-07-07
• xwkont:ref:gum-owl — GUM 3.1 OWL — verified absence of a dedicated change class directly against GUM-31.owl.txt, 2026-07-07

Review History

Review ID	Date	Outcome	Notes
—	2026-07-07	Draft created	Created after direct verification of all 8 source ontologies. The draft records GFO's remaining extended-change branch and SUMO's real InternalChange family, plus scoped absences in the other six sources.
—	2026-07-07	Passed — advanced draft → reviewed	Content originally drafted by Codex (external run, GPT-5.4-Mini, Extra-High reasoning) per the standing Codex-delegation process. Independently re-verified this session, directly against re-fetched primary artifacts: GFO's Change, Continuous_change, Intrinsic_change, Extrinsic_change, and the Process/Change owl:disjointWith pair, all confirmed verbatim against modules/gfo-base.owl (including the exact owl:equivalentClass pairing of each deprecated name to its surviving one -- Intrinsic_change to Continuous_change, Extrinsic_change to Instantaneous_change -- and both deprecated classes' owl:deprecated true flag); SUMO's InternalChange and StateChange confirmed verbatim against Merge.kif, including InternalChange's subclass Process declaration and its documented subtype family; BFO's and DOLCE's absence claims confirmed by direct grep of 21838-2/owl/bfo-core.ttl and DOLCE-Lite.owl (only informal "change"-as-verb usage found in both, no dedicated class); TUpper's absence claim confirmed by direct grep of tupper.all.owl and tupper.clif (zero occurrences of "change" in either). Found and fixed one defect in the Codex draft: the GFO Change row's source_claim_type was given as cross-reference, a value not in docs/INFORMATION_ARCHITECTURE.md's four-value claim-typing table (direct quotation, paraphrase, editorial observation, inference) and not an established repository convention (unlike non-equivalence, which is precedented across event.md/process.md/ ontological-level-stratum.md for absence rows) -- corrected to editorial observation, the correct type for a comparison XwkOnt draws from already-cited evidence. UFO's, YAMATO's, and GUM's absence claims were not independently re-fetched this session (a GUM fetch attempt failed on a dead archive redirect) and are carried from the Codex draft's own citations rather than freshly re-verified -- flagged in Future Work, not treated as fully closed. This crosswalk meets the reviewed-eligibility criterion (docs/methodology/crosswalk-runbook.md) on GFO alone: Change/Continuous_change are declared directly in gfo-base.owl, GFO's own base/core module, and that classification is directly verified against the primary artifact -- SUMO's second-source status is additional confirmed content, not a requirement for this advancement.
—	2026-07-07	Cross-reference update — three absences independently confirmed, no editorial_status change	Resolved uncertainty-005: UFO's, YAMATO's, and GUM's absence claims, previously carried unverified from the Codex draft, were independently re-fetched/re-extracted (a cached complete UFO 2021 full-text extraction, a freshly re-fetched and pdftotext-extracted YAMATO101216.pdf, and a freshly re-fetched GUM-31.owl.txt) and full-text searched for "change." All three confirmed absent as dedicated classes, despite substantial prose discussion in UFO (two subsections) and YAMATO (one subsection). editorial_status remains reviewed.

Future Work

• Decide whether the GFO/SUMO relation should stay related or be refined later if a source-side equivalence appears.
• If a later pass wants finer SUMO granularity, check whether StateChange or another child is the best canonical anchor.
• Keep event.md and process.md as cross-references for the instantaneous-reading and Process/Change-disjointness material, not duplicated source content.
• ~~UFO's, YAMATO's, and GUM's absence findings were not independently re-fetched during this session's review pass~~ — done 2026-07-07 (session-051): all three re-fetched and full-text searched for "change" independently, confirming the Codex draft's original claims (uncertainty-005 resolved).