Gellish dictionary files
The Gellish dictionary files can be downloaded free of charge from the download area of this website. Those files are themselves written in Gellish, which means that they are CSV files, each of which contains a collection of Gellish expressions conform the Gellish Syntax definition.
The taxonomic dictionary – ontology
The Gellish electronic dictionary is a special kind of dictionary because it not only defines concepts and their terminology, but it also defines the computer interpretable Gellish formalized natural language. This is achieved by first defining the Gellish Syntax that specifies the structure of Gellish expressions. Secondly by defining various kinds of relations between concepts and expressing those definitions conform the Gellish Syntax.
At its core, each concept is defined by a relation between the defined concept (the subtype) and one or more of its direct supertype concepts. For example creating sentences such as
“car <is a kind of> vehicle
Because this is done for each concept in the dictionary it makes that all concepts in the dictionary are arranged in one integrated subtype-supertype hierarchy. This implies that the subtype concepts inherit characteristics of their supertype concept(s). Such a dictionary is called a taxonomic dictionary. Furthermore, the dictionary includes modeled definitions of kinds of relations. Those relations can then be used for making expressions or sentences that express information. Finally the dictionary includes other relations between the concepts that express knowledge about what is by definition the case. This makes that the dictionary is also called an ontology. In this way the taxonomic dictionary-ontology defines a formalized language. By adding English names of all concepts and phrases for the kinds of relations, the dictionary defines formalized English. By adding terminology for other natural languages the dictionary defines the Gellish family of formalized languages. The full dictionary includes among others the kinds of roles and the allowed roles players (‘domain’ and ‘range’) of every defined kind of relation and a large number of application domain specific concepts. The dictionary is itself expressed as Gellish expressions in a collection of files conform to the Gellish syntax. This makes the dictionary and language definition computer readable for import in databases and systems. It is available free of charge in the download area.
The ‘formal language definition base’, the first domain of the Gellish dictionary, contains a hierarchy of definitions of kinds of relations, the kinds of roles that the related ‘objects’ in such relations play and the kind of ‘objects’ that are allowed to play such roles (‘objects’ can mean anything).
Kinds of relations are denoted in the dictionary by names as well as by synonym names, base phrases (Pb) and inverse phrases (Pi). The phrases are intended to be used in Formalized English expressions. For example, the phrase <is located in> can be used in expressions such as ‘The Eiffel Tower <is located in> Paris’. The inverse phrases denote the same kind of relation as the bases phrases, provided that the left hand and right hand terms are swapped.
A name of any defined kind of relation is meant to be neutral to a reading direction of an expression in Formalized English (despite that the name may suggest a reading direction). Thus a name only does not specify whether ‘A Rel B’ or ‘B Rel A’ is valid. Therefore, names of kinds of relations usually do not appear in expressions, but phrases are used instead. The full ontology defines the kinds of things that are allowed to play a first and a second role respectively in an expression. The phrase that is declared to be a base phrase (Pb) for a name corresponds in English to an expression with the first role player (A) on the left hand side and the second role player (B) on the right hand side of the phrase, thus <A Pb B>. The inverse phrase (Pi) corresponds to an inverse positions of A and B, thus <B Pi A> is equivalent to <A Pb B>. For example, the phrase <is located in> is an inverse phrase for the kind of relation with name “being located in a physical object”.
For a better understanding of a definition it is recommended to consult also the definition of the direct supertype(s) of a defined concept.
Each concept in the Gellish dictionary is identified by a Gellish unique identifier (UID), which is a character string that consists of a positive whole number, optionally preceded by a prefix followed by the separator colon (:). The standard prefix is Gel. For example the concept ‘relation’ is uniquely identified by UID 2850, or by UID Gel:2850. For software that prefers to refer to the concepts and terms by means of absolute URIs, such as RDF based software, it is allowed to refer to concepts using the prefix https://www.gellish.net/dictionary, followed by the sparator hash (#).
For example, the following UIDs are equivalent and all refer to the concept relation.
Every definition includes a subtype relation to a supertype concept (with another UID) that is arranged higher in the taxonomic hierarchy (the subtype-supertype hierarchy) of kinds, including also kinds of relations. All those kinds of relations are subtypes of the top kind of relation called ‘relation’. The strict taxonomy defines ‘inheritance’ of knowledge, requirements and definitions. Furthermore, it enables the verification of the semantic correctness of expressions by means of software for reasoning and drawing logical conclusions. One kind of relation may have more than one direct supertype kind of relation. In those cases there will be more that one textual definition, which slightly differ, while having the same meaning.
The book ‘Semantic Information Modeling in Formalized Languages‘ (2014) provides a systematic presentation and discussion of the taxonomy of kinds of relations in the Gellish dictionary as well as a definition of relevant kinds of contextual facts. It also describes semantic patterns and gives guidance on semantic modeling. The book ‘Semantic Information Modeling Methodology‘ provides further guidance on the application of the Gellish family of formalized languages.
The GitHub website contains a Gellish reference application that can read and write Gellish files and verify the quality of collections of Gellish expressions.