Ontology (redirected from ontologist)

ontology: see metaphysics.

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ontology

Theory of being as such. It was originally called “first philosophy” by Aristotle. In the 18th century Christian Wolff contrasted ontology, or general metaphysics, with special metaphysical theories of souls, bodies, or God, claiming that ontology could be a deductive discipline revealing the essences of things. This view was later strongly criticized by David Hume and Immanuel Kant. Ontology was revived in the early 20th century by practitioners of phenomenology and existentialism, notably Edmund Husserl and his student Martin Heidegger. In the English-speaking world, interest in ontology was renewed in the mid-20th century by W.V.O. Quine; by the end of the century it had become a central discipline of analytic philosophy. See also idealism; realism; universal.

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ontology

The structure of a system. A system model. The word refers to the branch of metaphysics that deals with the nature of reality or being. It therefore refers to "what exists" in a system: all elements within all category hierarchies and the relationships between them.

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ontology

1. Philosophy the branch of metaphysics that deals with the nature of being

2. Logic the set of entities presupposed by a theory

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1.	(philosophy)	ontology - A systematic account of Existence.
2.	(artificial intelligence)	ontology - (From philosophy) An explicit formal specification of how to represent the objects, concepts and other entities that are assumed to exist in some area of interest and the relationships that hold among them. For AI systems, what "exists" is that which can be represented. When the knowledge about a domain is represented in a declarative language, the set of objects that can be represented is called the universe of discourse. We can describe the ontology of a program by defining a set of representational terms. Definitions associate the names of entities in the universe of discourse (e.g. classes, relations, functions or other objects) with human-readable text describing what the names mean, and formal axioms that constrain the interpretation and well-formed use of these terms. Formally, an ontology is the statement of a logical theory. A set of agents that share the same ontology will be able to communicate about a domain of discourse without necessarily operating on a globally shared theory. We say that an agent commits to an ontology if its observable actions are consistent with the definitions in the ontology. The idea of ontological commitment is based on the Knowledge-Level perspective.
3.	(information science)	ontology - The hierarchical structuring of knowledge about things by subcategorising them according to their essential (or at least relevant and/or cognitive) qualities. See subject index. This is an extension of the previous senses of "ontology" (above) which has become common in discussions about the difficulty of maintaining subject indices.

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Ontology 

a subdivision of philosophy that studies universal principles of being, its structure and its laws. Essentially, ontology expresses a picture of the world that corresponds to a particular level in the knowledge of reality and that is recorded in a system of philosophical categories characteristic of a particular period and philosophical tradition (for example, materialism and idealism). In this sense, every philosophical and, in general, every theoretical system rests on certain ontological concepts that constitute its stable content foundation but that change as cognition develops.

The term “ontology” was first used in the philosophical lexicon (1613) of R. Goclenius (Germany) as a synonym for metaphysics. It gained currency in the school of C. Wolff, for whom ontology came to signify the primary fundamental part of metaphysics, concerned with definitions of being as such. Until the early 19th century, ontology developed on the basis of speculation and consisted chiefly of ideas concerning the hidden essences of things. The flimsiness of these teachings on being was criticized by German classical philosophy and was fully surmounted by Marxism, which demonstrated the necessary ties among and unity of ontology, epistemology, and logic and, consequently, the dependence of ontological concepts on the existing level and forms of cognition.

In the 20th century the heightened level of abstract scientific cognition has presented certain basic ontological problems—the construction of an adequate ontological interpretation of abstract concepts of modern science (for example, cosmology and the physics of elementary particles) and the creation of a theoretical foundation for modern methodological approaches and trends (for example, the ontological basis of a systems approach, or of cybernetics). The issue of ontology is discussed in contemporary Marxist literature. Although some Marxist philosophers believe that ontology is not entitled to an independent existence, others assert that it should be a special branch of dialectical materialism.

Attempts to restate problems of ontology in a new, primarily subjective, personal vein, as a matter of the strata and levels of being of the personality, are characteristic of a number of schools of modern bourgeois philosophy, particularly phenomenology, existentialism, and personalism. This line of thought reflects the world view of the pessimistic, alienated individual.

E. G. IUDIN