ONTOLOGY TERMINOLOGY

📘 ONTOLOGY TERMINOLOGY


📚 1. BEING & EXISTENCE

Being — the condition or status of whatever there is (the realm of entities and their natures).

Example: “Triangularity” as the attribute or nature that makes something a triangle (abstract aspect).

Existence — the property of an entity that it is instantiated in reality (the fact that something is present).

Example: The specific triangle drawn on this page (an existing, instantiated triangle).

Caveat: Some traditions treat "being" as broader than mere existence (includes possible/abstract entities); clarify your usage when necessary.


🧱 2. ENTITY & ARISTOTELIAN FOUR CAUSES

Entity — anything that can be referred to as an object of discourse (physical objects, events, properties, numbers, propositions).

Example: The capacitor on my desk is an entity.

Four Causes (Aristotle):

  • Material Cause — the matter out of which X is made.
    Example: Ceramic and aluminium for a capacitor's plates.
  • Formal Cause — the pattern, structure, or essence that makes X the kind of thing it is.
    Example: Two conductive plates separated by a dielectric in a capacitor.
  • Efficient Cause — the process or agent that brings X into being.
    Example: The manufacturing steps that assemble the capacitor.
  • Final Cause — the purpose or function for which X exists.
    Example: The capacitor’s role in storing charge to stabilize voltage.

🧍 3. INDIVIDUAL & UNIVERSAL

Individual (Particular) — a single, concrete or instantiated entity.

Example: The capacitor with serial #A123.

Universal — a property or type that can be instantiated by many individuals.

Example: The property being a capacitor or the type “capacitor.”

Note: Universals vs. particulars is an ontological debate (realist vs. nominalist). Here we use the standard realist-friendly wording.


⚙️ 4. ESSENCE & ACCIDENT

Essence — a set of properties an entity must have to be the kind it is (necessary conditions).

Example: Having three straight sides is essential to being a Euclidean triangle.

Accident — a contingent property an entity can gain/lose without ceasing to be the same kind.

Example: A triangle’s colour or size.


🪞 5. IDENTITY & PERSISTENCE

Identity — what it is for an entity to be the very same entity (criteria of sameness).

Example: The identity conditions of a person include continuity of a particular biological organism (one common criterion among many).

Persistence — how an entity continues to exist through time and change (accounts include endurantism and perdurantism).

Example: The “Ship of Theseus” raises the persistence question when planks are replaced.

Caveat: There are multiple theories (endurantism/perdurantism) — state which you adopt in downstream work.


🌱 6. POTENTIALITY & ACTUALITY

Potentiality — a dispositional or capacity-like state that can be realized under suitable conditions.

Example: A seed’s capacity to grow into a tree.

Actuality — the realized or manifest state of what was potential.

Example: The mature tree that grew from the seed.


📐 7. ABSTRACT & CONCRETE

Abstract — entities that are not spatiotemporally located and are not causally efficacious in standard ways (numbers, propositions).

Example: The number 7.

Concrete — spatiotemporally located entities that can causally interact.

Example: This apple on my table.


🔢 8. DISCRETE & CONTINUOUS

Discrete — composed of distinct countable units; elements separated by identity.

Example: Ten chairs in a room.

Continuous — a continuum not naturally divided into countable discrete units (modeled by continua).

Example: The volume of water in a river (modeled as a continuous quantity).


🪨 9. SUBSTANCE — FORM — MATTER

Substance — an entity that underlies properties and has ontological priority in some frameworks (the 'thing itself').

Example: The statue considered as a persisting object.

Form — the organizing principle or structure that makes matter into a particular kind.

Example: The statue’s shape (the arrangement making it a depiction of David).

Matter — the physical stuff composing an object.

Example: The marble from which the statue is carved.


🔔 10. OCCURRENCE

Occurrence — a single, time-bound event or instance of happening (token).

Example: The lightning strike at 14:02 UTC on 11 Dec 2025.


🌈 11. PHENOMENON

Phenomenon — an appearance or event as experienced (often used in epistemology/phenomenology).

Example: The rainbow observed after rain — the perceptual phenomenon.


🔄 12. STATE — EVENT — PROCESS

State — a condition or property of an entity at a time.

Example: Water in the solid state (ice) at 0°C.

Event — an occurrence that effects change between states.

Example: Melting begins at time t₀.

Process — a sequence of events or state-changes extended through time.

Example: The entire water cycle: evaporation → condensation → precipitation.


🎛️ 13. DISPOSITION & CAPABILITY

Disposition — an intrinsic tendency or propensity under circumstances (often modal).

Example: Glass’s disposition to shatter when struck.

Capability (Ability) — the power to perform an action (can be realized via skills, mechanisms).

Example: A human’s capability to speak (language competence).


🧭 14. MODALITY

Modality — modes of truth or being: possibility, actuality, necessity.

  • Possible: true in at least one possible world.
  • Actual: true in the actual world.
  • Necessary: true in all possible worlds.

Example: “2+2=4” is necessary; “It may rain tomorrow” is possible.


📊 15. QUANTITY & QUALITY

Quantity — measure or count of how much / how many (numerical magnitude).

Example: 5 kilograms.

Quality — attributes describing kinds or features (non-numeric properties).

Example: The apple’s redness.


🗺️ 16. SPACE — TIME — FORCE

Space — the dimension or region in which objects are located (geometric/spatial relations).

Example: The coordinates of a room.

Time — the ordering dimension of events (temporal sequence).

Example: 11:00 AM on 2025-12-11.

Force — (in physics) an interaction that causes acceleration or state-change.

Example: The push that accelerates a block.


📈 17. FUNCTION & PERMUTATION

Function — a mapping from inputs to outputs (mathematical/semantic mapping).

Example: f(x) = x² maps 2 → 4.

Permutation — a bijective rearrangement of elements of a set.

Example: Reordering (A,B,C) → (C,A,B).


🔐 18. CONDITION & CONSTRAINT

Condition — one or more requirements that must obtain for a fact/event to occur (enabling).

Example: Presence of oxygen as a condition for combustion.

Constraint — limitation that restricts the possible states or evolutions.

Example: Fuel capacity limits fire duration.


🧩 19. MEREOLOGY — PARTS, WHOLES & RELATED NOTIONS

Part — an entity that is included within another (the whole).

Example: Wheel is a part of a car.

Whole — entity composed of parts in a certain structure.

Example: The car.

Proper Part — part distinct from the whole (not identical).

Example: Engine is a proper part of the car.

Overlap — two entities share at least one common part.

Example: Two adjacent plots share a border segment.

Fusion / Sum — the object that is the mereological sum of given parts.

Example: The collection of all bricks forming a wall considered as one object.

Caveat: Mereological theories vary (classical mereology vs. non-standard approaches). State which mereology you adopt if precision matters.


🧲 20. ONTOLOGICAL DEPENDENCE & RELATED NOTIONS

Existential Dependence — A depends on B for its existence (A cannot exist unless B does).

Example: A hole depends existentially on the object (a hole cannot exist without its host).

Constitution — relation where one entity (constituted) is made of another without identity (statue constituted by lump of clay).

Example: The statue is constituted by the lump, though some argue they are identical—philosophers disagree.

Supervenience — higher-level properties are fixed by lower-level properties (no change at higher-level without change at lower-level).

Example: Mental properties supervene on neural properties (standard formulation in philosophy of mind).


🕰️ 21. IDENTITY THEORIES (ADVANCED)

Endurantism (3Dism) — objects are wholly present at each moment of their existence.

Example: A chair exists wholly at t₁ and t₂.

Perdurantism (4Dism) — objects persist by having temporal parts (time-slices).

Example: "You-at-age-5" is a temporal part of you.

Counterpart Theory — across possible worlds identity is represented by counterparts rather than strict identity.

Example: Your counterpart in another possible world is not you but a similar individual.


🌍 22. POSSIBLE WORLDS & MODAL ONTOLOGY

Possible World — a complete way the world might have been (a maximal state).

Example: A possible world where Rome never fell.

Actual World — the world we inhabit (the world considered actual).

Example: Our world.

Necessity / Contingency / Possibility — standard modal categories (see Modality above).

Impossible Worlds — sometimes posited for handling contradictions or intensional contexts (non-standard).

Example: A "world" where square circles exist (use with caution; non-classical frameworks).


📦 23. CATEGORY THEORY / ABSTRACT STRUCTURE (FOUNDATIONS)

Object (categorical) — an abstract node in a category.

Example: A set A in category SET.

Morphism — arrow from one object to another preserving structure.

Example: f: A → B.

Functor — map between categories preserving structure.

Example: A functor sending each graph to its adjacency matrix.

Natural Transformation — a morphism between functors that is 'natural' in its components.

Example: A canonical reindexing map between two functorial constructions.


🧬 24. FORMAL ONTOLOGY (BFO / DOLCE) — SELECT NOTIONS

Continuant — an entity that endures through time while retaining identity (3D-ish notion used in BFO).

Example: A human organism.

Occurrent — an event or process that unfolds in time.

Example: A concert.

Dependent Continuant — a property that cannot exist without a bearer.

Example: The colour of a leaf depends on the leaf.

Quality Region — domain of a quality (e.g., temperature scale).

Example: Temperature values 0–100°C.

Process Boundary — an instantaneous boundary marking process change (modeling device).

Example: The exact instant water crosses boiling point in an experiment.


🖥️ 25. AI & COMPUTATIONAL ONTOLOGY (APPLIED NOTIONS)

Class (Type) — set of individuals sharing core properties.

Example: Class Vehicle.

Instance (Individual) — concrete member of a class.

Example: Car VIN 1HGBH41JXMN109186.

Object Property (Relation) — relation between individuals.

Example: partOf(wheel, car).

Data Property — relation between an individual and a data value.

Example: car.maxSpeed = 180 (km/h).

Reasoner — software component that derives implicit facts from explicit axioms (ontology inference).

Example: An OWL reasoner deriving that all humans are mammals given axioms.


⚛️ 26. METAPHYSICAL STRUCTURE & ONTOLOGICAL LEVELS

Fundamental Level — the ontology layer considered metaphysically basic (varies by theory).

Example: In physics, fundamental fields or particles.

Emergence — phenomena at higher levels arising from but not reducible to lower-level organization.

Example: Wetness emerges from H₂O molecular interactions.

Grounding — metaphysical dependence: facts obtaining in virtue of more fundamental facts.

Example: The fact "the apple is red" grounded in surface reflectance microstructure.

Natural Kinds / Artifact Kinds — distinction between naturally occurring categories and human-made kinds.

Example: Electron (natural kind) vs. Smartphone (artifact).


🔬 27. SCIENTIFIC ONTOLOGY (MODELS)

Field Ontology — modeling reality as continuous fields (physics).

Example: Electromagnetic field.

System Ontology — entities defined by interacting components (systems theory).

Example: The cardiovascular system.

Computational Ontology — describing phenomena as information structures.

Example: Gene sequences represented as digital data.


📜 28. META-ONTOLOGY

Quinean Criterion — ontological commitments arise from quantification in best theory ("To be is to be the value of a bound variable").

Example: If your science quantifies over electrons, you are committed to electrons.

Neo-Aristotelian / Grounding Approaches — focus on explanation in terms of substances and grounds.

Example: Explaining biological function in terms of organismal roles.

Ontological Commitment — what entities a theory posits as existing.

Example: Committing to spacetime points vs. fields in physics.


🧴 29. ADVANCED SEMANTIC TERMS

Trope — a particular instance of a property (particularized property).

Example: The particular redness of this apple (not the universal 'redness').

Event Token vs. Event Type — token = particular occurrence; type = general kind.

Example: Token: the 2005 explosion in Lab A; Type: 'explosion'.

Intension vs. Extension — intension = concept/meaning; extension = set of instances.

Example: Intension of 'prime number' vs. its extension {2,3,5,7,...}.



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