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reality domain”), Gruber's definition falls under the framework of knowledge-based
systems. What
is
, what
exists,
relates therefore to what can be
represented
[GRU 93].
In the field of information systems, Chen [CHE 76] relies on an ontology made
up of three fundamental elements, entities, attributes and relationships in order to
develop what he calls an “entity-relationship modeling”. For him, the entities
designate “things” that are identifiable, distinguishable from their environment and
that correspond to “objects” in Smith's terminology. In order to illustrate the
different terms of this ontology, let us consider the example of the school domain in
which students and schools represent two types of “objects-entities”. The attributes
describe the characteristics of these “objects-entities” (for example, for junior high
schools, the public/private status, the results from the French “brevet” national
exam). These attributes correspond to Smith's “properties”. The relationships
concern on the one hand the links between the “objects-entities” and their attributes
(schools are, for example, public or private, have such number of pupils, etc.), on the
other hand between “objects-entities” of different nature (such student attends such
school), or even between different attributes (the results of the French “brevet” are
better in such type of school) and finally the links between “objects-entities” of the
same nature (exchanges between same class students, proximity between schools or
flow of pupils changing schools).
These different points of view formulated, respectively, by philosophers,
computer scientists and information systems specialists, converge in their ambition
to describe the world/a world using a generic conceptualization, but it is interesting
to point out the nuances in their approaches. In this way, differences of opinion exist
between philosophers and computer scientists about the ontologies. The fact that the
objects do not necessarily constitute the favored input for philosophers when it is
often the case in computer science is an example. Indeed, for philosophers,
processes, for example, could replace them [LIV 09]. Smith [SMI 98] for his part,
clarifies the difference in point of view between philosophers and “information
scientists” by distinguishing a “reality-based” ontology that has an objective to
describe the world in its “reality” and an ontology that he qualifies as
epistemological and that is associated with a particular conceptualization of the
world (among others). In addition, Peuquet [PEU 02] points out that Chen [CHE 76]
presents his three fundamental concepts and their articulation at the center of his
entity-relationship model without making reference to the philosophical literature on
ontologies. This approach was then developed in a progressive and autonomous
manner in the field of computer science to build a “theory of database model
design”. This perspective of the
model design,
representative of computer science,
implies a
bottom-up
approach, while the philosopher falls instead under a
top-down
