The unique name assumption is a simplifying assumption made in some
ontology
In metaphysics, ontology is the philosophical study of being, as well as related concepts such as existence, becoming, and reality.
Ontology addresses questions like how entities are grouped into categories and which of these entities ...
languages and
description logics. In logics with the unique name assumption, different names always refer to different entities in the world.
It was included in
Ray Reiter's discussion of the
closed-world assumption The closed-world assumption (CWA), in a formal system of logic used for knowledge representation, is the presumption that a statement that is true is also known to be true. Therefore, conversely, what is not currently known to be true, is false. Th ...
often tacitly included in Database Management Systems (e.g. SQL) in his 1984 article "Towards a logical reconstruction of relational database theory" (in M. L. Brodie, J. Mylopoulos, J. W. Schmidt (editors), Data Modelling in Artificial Intelligence, Database and Programming Languages, Springer, 1984, pages 191–233).
The standard ontology language
OWL does not make this assumption, but provides explicit constructs to express whether two names denote the same or distinct entities.
OWL Web Ontology Language Reference
/ref>
* owl: sameAs is the OWL property that asserts that two given names or identifiers (e.g., URIs) refer to the same individual or entity.
* owl:differentFrom is the OWL property that asserts that two given names or identifiers (e.g., URIs) refer to different individuals or entities.
See also
* Closed-world assumption The closed-world assumption (CWA), in a formal system of logic used for knowledge representation, is the presumption that a statement that is true is also known to be true. Therefore, conversely, what is not currently known to be true, is false. Th ...
* Coreference
References
Knowledge representation
Ontology (information science)
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