An entity is something that exists. In its broadest sense, the concept is the most general category of being and encompasses anything that is identifiable, including living beings, inanimate objects, places, events, ideas, numbers, properties, and relations. It is controversial whether empty space and absences, such as holes or shadows, are also entities or should be regarded as nonentities. The words object, thing, and being are often treated as synonyms for entity, but they have distinct connotations and are not always interchangeable.
Various fundamental types of entities have been proposed, but it is disputed whether they are all part of reality. Particulars are individual, nonrepeatable entities, such as a specific apple. They contrast with universals, which are general, repeatable entities, such as the color red. Concrete entities exist in space and time and causally interact, such as a cat, which is not the case for abstract entities, such as the number 7. Independent entities exist on their own, whereas dependent entities require or are grounded in other entities. Other suggested types include possible, actual, and necessary entities; observable and unobservable entities; and fictional and intentional entities.
Entities are typically treated as having an identity that distinguishes them from other entities, expressed in the principle "no entity without identity". Questions of identity are closely connected to composition and boundaries: some entities are composed of smaller entities, such as a table made up of a tabletop and legs, while boundaries separate entities from each other, marking where one thing ends, and another begins.
The concept entity is relevant to many fields. Metaphysics and ontology study what an entity is, which entities exist, and how they may be divided into categories of being. Philosophy of language, philosophy of mind, and epistemology discuss how linguistic representations or mental processes refer to entities. Information science and computer science are interested in how information about entities is stored in knowledge bases. More specific uses of the term entity are found in the fields of law, economics, accounting, politics, chemistry, and medicine. Philosophical discussions of the nature of entities and related concepts originated in antiquity, particularly in ancient Greek and Indian thought.
Definition
An entity is something that exists, such as a material object or living being. Entities are often regarded as having separate or independent existence, each with its own identity, distinct from other entities. In its broadest sense, the concept encompasses all identifiable items. This can include inanimate everyday objects, people, events, places, ideas, relations, facts, universal entities such as the color red, abstract objects such as the number 7, and collective entities such as sets. Accordingly, the concept entity is often treated as the broadest category of being, covering everything that is or could be. Some definitions provide narrower characterizations that require additional conditions, for example, that entities are stable, have clear boundaries, are indivisible, or serve as distinct objects that can be counted.
Entities contrast with nonentities, although it is controversial to what this concept applies. Suggested examples of nonentities include voids, emptiness, nothingness, and absences, such as holes or shadows. Similarly, philosophers debate whether nonexistent objects, such as the winged horse Pegasus, should be regarded as entities. Another set of challenges comes from parts or aspects of reality that are not clearly identifiable, for example because they lack exact boundaries or cannot be precisely distinguished from other entities. The terms reification and hypostatization can denote the practice of treating a nonentity as if it were an entity.
The English word entity has its roots in the Latin term , meaning . It gave rise to the Latin word and was subsequently adopted into French as the term . The French word was borrowed into English in the 16th century, with the earliest known use in 1596 in a work by Thomas Bell.
Related concepts The terms object, thing, and being are commonly used as synonyms of entity. However, they carry distinct connotations and are sometimes used differently.
An object is something toward which thought, perception, or intention is directed. In a broad sense, objects encompass all items apprehended, imagined, or referred to, including not only physical objects but also fictional ones without real counterparts, such as unicorns. In a narrower sense, the term is sometimes limited to material entities that can be perceived by the senses. A common distinction contrasts objects with subjects. It holds that while objects are grasped in consciousness, they do not possess it: an object is an it that can appear in someone's consciousness, whereas a subject is a self that acts as a center of consciousness.
Understood broadly, a thing is any item whose existence is acknowledged, including but not limited to material bodies. In this regard, the word thing is the broadest countable noun, reflecting the slogan "everything is a thing". However, the term is also used in more restricted ways to denote an individual entity in contrast to the properties it has or the relations it bears to other things. In this sense, a car is a thing, whereas its shape, color, and weight are features or aspects rather than things in their own right. In everyday discourse, the term thing is often used for inanimate objects, such as rocks or chairs, contrasting with living creatures, such as humans and other animals.
When used as a countable noun, the expression a being overlaps with that of an entity, denoting something that exists. However, being is also used as an uncountable noun, referring to the fact that something is, to existence as such, or to the totality of reality. The distinction between being and beings played a central role in the philosophy of Martin Heidegger, who termed it the ontological difference. He argued that being constitutes the background context that makes all individual beings intelligible, insisting that being is not itself an individual being. Traditionally, being is contrasted with becoming. In this sense, being denotes stable or permanent aspects of reality, whereas becoming covers changes and processes.
Types Many types of entities are discussed in the academic discourse. Different classifications may overlap, and it is controversial whether all proposed categories represent genuine entities.
Particular and universal
Particulars are individual entities: they are unique and non-repeatable. They contrast with universals, which are general and repeatable entities. For example, the philosopher Socrates, the Great Pyramid of Giza, and the planet Mars are particular entities, whereas the color blue, the shape of a square, and the property of being a flower are universal entities. A key difference is that each particular exists as an individual instance, whereas universals can have multiple instances and be present in several locations at the same time. Universals can express repeatable aspects of particulars. For example, the particulars Mars and Jupiter are both characterized by the universal of being a planet. According to a common view, particulars instantiate universals but are not themselves instantiated by anything else.
Universals are frequently understood in terms of properties and relations. A property is an entity that expresses a quality or feature of another entity. For example, the property being-tall is a feature of the Empire State Building. A relation is an entity that expresses how several things stand to each other. For instance, the relation being-taller-than is an entity that characterizes how the Empire State Building stands to the White House. Although properties are typically treated as universal entities that can have multiple instances, an alternative approach treats them as particulars, called tropes, regarding each individual instance as a separate entity.
Various metaphysical debates address the reality of universals, asking whether they exist as genuine entities. Platonic realists assert that universals can exist independently of particulars, while moderate realists hold that they exist only when instantiated by particulars. Conceptualists maintain that universals exist only in the minds of individuals as conceptual entities but not in mind-independent reality, whereas nominalists deny that universals in either form are real.
Concrete and abstract
Concrete entities are things that exist in space and time. They can undergo changes, causally interact with other entities, and be perceived or measured, either directly or indirectly. They contrast with abstract entities, which have no physical location or temporal duration. Accordingly, abstract entities do not undergo changes, do not causally interact with other entities, and are not accessible to sensory perception. For example, a tree, a house, and an earthquake are concrete entities, whereas the number 7, the empty set, and the proposition "snow is white" are abstract entities.
Concrete entities can be distinguished by the field of inquiry that studies them, including physical, biological, psychological, and social entities, such as a rock, a bird, an idea, and a financial institution, respectively. According to one view, the different domains belong to distinct levels of reality. This outlook suggests that higher-level entities emerge from lower-level entities, depend on them, and show new forms of organization, as in the claim that mental states emerge from physical brains.
While the existence of concrete entities is widely accepted, it is controversial whether abstract entities are genuine constituents of reality. Proponents argue that abstract entities are indispensable to scientific descriptions of the world and that many domains of discourse refer to them as if they were distinct entities. Opponents question in what sense entities outside spacetime and without causal relationships could exist, and how humans, who are themselves concrete entities, could know about them.
Independent and dependent Independent entities exist on their own without relying on other entities. They contrast with dependent entities, which require other entities or are grounded in them. Philosophical discussions concern whether there are dependent entities in addition to independent ones, and which entities fall under each category. For example, one view identifies independent entities with substances, conceived as particulars that underlie and support properties and relations. On this view, substantial entities such as a tomato are independent, whereas their features are dependent, such as the idea that the redness of a tomato depends on the tomato because it inheres in the tomato. A different suggestion holds that macroscopic objects encountered in everyday life, such as chairs, are dependent on the microscopic objects, such as the elementary particles that constitute them.
The contrast between independent and dependent entities overlaps with that between major and minor entities. Major entities are regarded as having a more substantial or robust existence, such as material objects and events. They contrast with minor entities, which are considered subordinate in some sense, such as surfaces, holes, and shadows. For example, the surface of an apple has one spatial dimension less than the apple and cannot exist without the apple, making it less substantial. Similarly, a hole in a cheese or a shadow cast by a person is regarded as less robust since it involves an absence of matter or light rather than a positive physical presence. Absences are also called negative entities, and it is controversial whether they should be regarded as genuine but dependent entities or as nonentities.