What is a semantic reasoner?
A semantic reasoner is also known as a rules engine, a reasoning engine, or a reasoner. This software is capable of inferring logical consequences from the available set of axioms or asserted facts.
Semantic reasoners essentially generalize the notion of inference engines by virtue of offering a richer set of mechanisms to perform operations with.
An ontology language and a description logic language is usually used for the purpose of specifying the inference rules used by semantic reasoners. A lot of semantic reasons carry out reasoning tasks by employing first-order predicate logic.
This involves the inference being proceeded by forward chaining and backward chaining.
Probabilistic reasoners like probabilistic logic networks and non-axiomatic reasoning systems also exist.
What are ontologies?
An ontology is a set of concepts within a domain and the relationships between them. It involves formally specifying the components like individuals (instances of objects), classes, attributes, and relations along with rules, axioms, and restrictions.
Ontologies create a sharable and reusable knowledge representation and can even add new knowledge to the domain.
OWL is an example of an ontology language. It is essentially a semantic web computational logic-based language. OWL was designed for the purpose of representing rich and complex knowledge about things and the relations between them.
It enriches ontology modeling in semantic graph databases (RDF triplestores). When used in tandem with an OWL reasoner in these RDF triplestores, it can detect logical inconsistencies and also check whether there are any classes that cannot have instances.