Background-assumptions in knowledge representation systems Center for Cultural Informatics, Institute of Computer Science Foundation for Research and Technology - Hellas Heraklion, Crete, September 24, 2015 Maria Daskalaki

Building Ontology Ontology’s initial objective:Ontology’s initial objective: “ to reduce or eliminate conceptual and terminological confusion and come to a shared understanding” (Uschold, Gruninger, 1996, p. 94). Application of ontology so far:Application of ontology so far: different groups of conceptual modellers and ontology engineers use different jargon in order to describe a certain subject matter.  A “global knowledge network” (Doerr,Iorizzo, 2008) as an unfulfilled dream?

Our point of view implicit philosophical assumptions  Some of the difficulties emerging in the field of KR might be resolved if we shed light on the implicit philosophical assumptions that are hidden within the process of building ontologies. confusions  The first step towards this is to clarify some confusions, which seem to hamper the goal of building a global KR system.

“Retrospection” McCarthy1980: McCarthy=>ontology as a list of everything that exist. Sowa1984: Sowa=>need for cooperation between philosophy and computer sciences on the basis of an ontology. Genesereth and NilssonGenesereth and Nilsson=> “a conceptualization is an abstract, simplified view of the world” Gruber 1993: Gruber=> ontology is an “explicit specification of a conceptualization” Guarino1998: Guarino => “an ontology is a logical theory accounting for the intended meaning of a formal vocabulary, i.e. its ontological commitment to a particular conceptualization of the world”

Retrospection  Despite the great efforts in establishing and developing ontology in computer sciences, they do not seem to meet all the requirements of ontology!

Confusions in ontology  1 st confusion:functions  1 st confusion: functions ascribed to ontology: To maintain the cognitive content of the material represented. To reduce, as far as possible, the risk of misinterpretation of the content transmitted. To allow, via a shared conceptualization, communication between the members involved (users, machines, different fields,different models of KR) in the digital world.

1 st confusion: functions 1 st function: ontology as a descriptive source of knowledge: =>it does not allow for sound and complete reasoning. 2 nd function: reduction of the subjective interpretations: =>two alternatives: either finite computable functions or partial release from the request for compatibility. 3 rd function: communication: =>communication as a one-dimensional act/ communication as interaction

2 nd confusion: Domain According to Garbacz and Trypuz : “the description of the domain of an applied ontology corresponds, mutatis mutandis, to the philosophical characterization of the concept of being”. “In knowledge representation the range of entities which a given applied ontology commits to depends on a particular engineering problem that this ontology is to solve. Thus, its domain […] will contain those entities that in the view of the developer(s) of this ontology we need to posit in order to solve this problem ”. (Garbacz and Trypuz, 2013, p.9)

2 nd confusion: Domain  Domain itself, which is the “physical object” (i.e. being) of the ontologies seems to depend on a subjective factor, which calls into question the intersubjectivity that is one of the main goals of building ontologies! Background-assumption: the “objects” of reference in knowledge representation systems are not the physical objects and their relationships but rather the sphere of knowledge and information, which is independent of physical objects.

Philosophy and KR-systems  Need for reference to an external criterion.  “Dialectical relationship” as a dynamic process which takes into account the real object that is represented and questions the viewpoint of the specific sciences, from which we derive the knowledge to be represented.  Verification/falsification of our categorization.  Ontology as “recipes of Knowledge” representing aspects and behaviors of the objects of our perception!

Thank you!