Entity

An entity is a thing in the universe that can be identified by its distinct properties (such as space time location).

• Context:
  • It can (often) have an Entity Property (e.g., mass, location, or type).
  • ...
  • It can range from being a Physical Entity (e.g., a rock or a person) to being an Abstract Entity (e.g., a mathematical concept, a legal construct, or a Digital Twin).
  • It can range from being a Static Entity (e.g., a constant object) to being a Dynamic Entity (e.g., a process or event that changes over time).
  • It can range from being an Atomic Entity (e.g., a single atom) to being a Composite Entity (such as a system made up of interacting parts).
  • It can range from being a Persistent Entity (e.g., a mountain that remains over time) to being a Transitory Entity (e.g., a sound that exists only momentarily).
  • It can range from being a Referent Entity (be referenced in communication) to being a Referencing Entity (such as a word that points to another entity).
  • It can range from being a Named Entity (e.g., "Paris," "Albert Einstein") to being an Unnamed Entity (e.g., an unnamed animal in a forest).
  • It can range from being a Composite Entity (e.g., a complex system with many sub-entities) to being a Simple Entity (e.g., an isolated object).
  • It can range from being a Domain-Specific Entity (e.g., a legal entity or a biological species) to being a General Entity with broad applicability.
  • ...
  • It can be in a Causal Relation with another Entity (e.g., causing an effect or being influenced by another).
  • It can be an Individual from a specific Domain (e.g., a person in the legal domain, or a molecule in the chemical domain).
  • It can participate in Relational Structures (e.g., being a Referent Entity in communication or a Causal Entity influencing or being influenced by another).
  • It can be represented in a Digital Environment (e.g., as a Digital Twin or a Virtual Character).
  • It can be an Instance of a Concept Class (e.g., a particular book as an instance of the "book" class).
  • ...
• Example(s):
  • Physical Entities, such as:
    • Living Organisms, such as:
      • Persons (e.g., Aristotle).
      • Horses (e.g., Bucephalus).
      • Cellular Organisms (e.g., a single E. coli bacterium).
    • Inanimate Physical Objects, such as:
      • Books (e.g., the copy of “The Republic" that sat in Aristotle's library).
      • Buildings (e.g., The Eiffel Tower).
      • Vehicles (e.g., a Tesla Model S).
      • Natural Structures (e.g., Mount Everest).
    • Composite Physical Entities, such as:
      • Citys (e.g., Paris).
      • Manufacturing Plants (e.g., a Ford automotive factory).
  • Abstract Entities, such as:
    • Concept Classes (e.g., people, horses, books).
    • Time Periods (e.g., February 20, 2007).
    • Bibliographic Entities (e.g., a citation for an academic paper).
    • Mathematical Concepts (e.g., the number pi or a vector space).
  • Digital Entities, such as:
    • Files on a computer system (e.g., a PDF document or digital image).
    • Virtual Characters in a video game (e.g., an avatar in World of Warcraft).
    • Websites (e.g., Wikipedia.org).
  • Semantic Entities, such as:
    • Ontology Concepts in a Knowledge Representation System (e.g., the Person concept in the FOAF Ontology).
    • Terms in a thesaurus (e.g., synonym).
    • Semantic Annotations for a web resource.
  • Events, such as:
    • Historical Events (e.g., The signing of the Declaration of Independence).
    • Natural Phenomena (e.g., A solar eclipse).
    • Sporting Events (e.g., The 2020 Olympics).
  • Hypothetical Entities, such as:
    • Theoretical Constructs (e.g., Schrödinger’s cat).
    • Scientific Models (e.g., The Standard Model of Particle Physics).
  • Persistent Entities, such as:
    • Relational Database Tables that retain data over time.
    • Ontology Concepts used in a Semantic Web Framework.
  • Images, such as The Mona Lisa hanging in The Louvre.
  • ...
• Counter-Example(s):
  • A Relation (e.g., "go(subject, object)" or "eat(subject, object)") that defines interactions between entities but is not itself an independent entity.
  • A Property (e.g., "color," "size") that is a characteristic of an entity but does not exist as an entity in itself.
  • A Function or Mathematical Operation, such as "f(x) = x^2" that describes a relation but lacks independent existence.
• See: Concept Class, Named Entity, Event, Abstraction, Physical Entity, Digital Entity, Legal Fiction, Ontology Concept.

---

---

References

2014

• (Wikipedia, 2014) ⇒ http://en.wikipedia.org/wiki/Entity Retrieved:2014-11-4.
  • An entity is something that exists in itself, actually or hypothetically. It need not be of material existence. In particular, abstractions and legal fictions are usually regarded as entities. In general, there is also no presumption that an entity is animate.

    Sometimes, the word entity is used in a general sense of a being, whether or not the referent has material existence, e.g., is often referred to as an entity with no corporeal form (non-physical entity), such as a language. It is also often used to refer to ghosts and other spirits.

    The word entitative is the adjective form of the noun entity. Something that is entitative is "considered as pure entity; abstracted from all circumstances", that is, regarded as entity alone, apart from attendant circumstances.

2009

• WordNet.
  • that which is perceived or known or inferred to have its own distinct existence (living or nonliving)
• Wiktionary http://en.wiktionary.org/wiki/entity
  • That which has a distinct existence as an individual unit. Often used for organisations which have no physical form; An existent something that …

---