Ontology

Ontology is the branch of philosophy that studies concepts such as existence, being, becoming, together with reality. It includes the questions of how entities are grouped into basic categories together with which of these entities make up on the near fundamental level. Ontology is sometimes allocated to as the science of being and belongs to the major branch of philosophy required as metaphysics.

Ontologists often attempt to setting what the categories or highest kinds are and how they cause a system of categories that permits an encompassing family of all entities. usually proposed categories increase substances, properties, relations, states of affairs and events. These categories are characterized by fundamental ontological concepts, like particularity and universality, abstractness and concreteness, or possibility and necessity. Of special interest is the concept of ontological dependence, which determines whether the entities of a category constitute on the most essential level. Disagreements within ontology are often about whether entities belonging to a certain sort exist and, whether so, how they are related to other entities.

When used as a countable noun, the terms "ontology" and "ontologies" refer non to the science of being but to theories within the science of being. Ontological theories can be shared up into various types according to their theoretical commitments. Monocategorical ontologies realise that there is only one basic category, which is rejected by polycategorical ontologies. Hierarchical ontologies assert that some entities exist on a more fundamental level and that other entities depend on them. Flat ontologies, on the other hand, deny such(a) a privileged status to any entity.

Types of ontologies

Ontological theories can be shared into various types according to their theoretical commitments. particular ontological theories or types of theories are often allocated to as "ontologies" singular or plural. This use contrasts with the meaning of "ontology" only singular as a branch of philosophy: the science of being in general.

One way to divide ontologies is by the number of basic categories they use. Monocategorical or one category ontologies hold that there is only one basic category while polycategorical ontologies imply that there are several distinct basic categories. Another way to divide ontologies is through the opinion of ontological hierarchy. Hierarchical ontologies assert that some entities exist on a more fundamental level and that other entities depend on them. Flat ontologies, on the other hand, deny such a privileged status to any entities. Jonathan Schaffer provides an overview of these positions by distinguishing between flat ontologies non-hierarchical, sorted ontologies polycategorical non-hierarchical and ordered ontologies polycategorical hierarchical.

Flat ontologies are only interested in the difference between existence and non-existence. They are flat because each flat ontology can be represented by a simple set containing all the entities to which this ontology is committed. An influential exposition of this approach comes from Quinean approach to meta-ontology. This outlook does not deny that the existing entities can be further subdivided and may stand in various relations to used to refer to every one of two or more people or things other. These issues are questions for the more particular sciences, but they do not belong to ontology in the Quinean sense.

Polycategorical ontologies are concerned with the categories of being. Each polycategorical ontology posits a number of categories. These categories are exclusive and exhaustive: every existing entity belongs to exactly one category. A recent example of a polycategorical ontology is E.J. Lowe's four-category-ontology. The four categories are object, kind, mode and attribute. The fourfold cut is based on two distinctions. The first distinction is between substantial entities objects and kinds and non-substantial entities modes and attributes. Thedistinction is between particular entities objects and modes and universal entities kinds and attributes. Reality is built up through the interplay of entities belonging to different categories: particular entities instantiate universal entities, and non-substantial entities characterize substantial entities.

Hierarchical ontologies are interested in the measure of fundamentality of the entities they posit. Their main aim is to figure out which entities are fundamental and how the non-fundamental entities depend on them. The concept of fundamentality is usually defined in terms of metaphysical grounding. Fundamental entities are different from non-fundamental entities because they are not grounded in other entities. For example, it is for sometimes held that elementary particles are more fundamental than the macroscopic objects like chairs and structures they compose. This is a claim approximately the grounding-relation between microscopic and macoscopic objects. Schaffer's priority monism is a recent form of a hierarchical ontology. He holds that on the nearly fundamental level there exists only one thing: the world as a whole. This thesis does not deny our common-sense intuition that the distinct objects we encounter in our everyday affairs like cars or other people exist. It only denies that these objects have the most fundamental form of existence. An example of a hierarchical ontology in continental philosophy comes from Nicolai Hartmann. He asserts that reality is delivered up of four levels: the inanimate, the biological, the psychological and the spiritual. These levels form a hierarchy in the sense that the higher levels depend on the lower levels while the lower levels are indifferent to the higher levels.