Yesterday I discussed with Ansgar about some Ontology Design Patterns, and we encountered an issue with the Information Realization pattern from ontologydesignpatterns.org and Dolce Ultra Light (DUL).
In the original pattern InformationRealization is a subclass of
realizes some InformationObject.
In DUL, however, InformationRealization is also defined as being equivalent to
PhysicalObject or (Event and hasParticipant some PhysicalObject) and realizes some InformationObject.
In other words, it is either a PhysicalObject that realizes some InformationObject, or it is an event in which some PhysicalObject participates that realizes the InformationObject. This definition makes sense, since some performance on a specific date and at a specific place indeed realizes some InformationObject, e.g., Goehte’s Faust.
Anyway, this definition also seemed to us, at least, problematic, since it is not clear anymore whether an information realization is an object or an event. We tried to model what the underlying patter should be, and came up with the following.
We came to the conclusion that information realization always consists of both an event and at least one object, which is depicted in the lower part. Both are involved in realizing the information. For example, in the case of the Mona Lisa, it is not only the painting that realizes the Mona Lisa, but it is the painting participating in the event of its existence that realizes the Mona Lisa. Obvioulsy, this particular view is still debatable, since it would also be a possible interpretation that both Da Vinci and the painting participating in the event of the creation of the painting are the realization. In both cases there are, however, both an object and an event involved. In other words, even when intuitively the object realizes some information, it is actually the participation of some object in an event that realizes the information. This view is even supported by one of the most fundamental axioms of DUL, namely that there is no object without an event, and vice versa. Therefore we know that this event must exist.
However, using only the event as the InformationRealization does also not suffice, since not all participating objects necessarily realize the information. Take the performance of Goethe’s Faust as an example. There is clearly the actors that realize the act, although both the actors and the audience participate in the event of the play. In other acts, such as the Rocky Horror Picture Show the audience might, however, play a role, and some interaction between audience and actors takes place. In such cases at least some audience members actualy contribute to the realization.
In the final pattern, we decided to keep the class InformationRealization for convenience reasons.
Our pattern, while more complete, is also more complex and less intuitive. Therefore, we concluded that it might not always be reasonable to instantiate the full pattern and chose the middle way. We include both, making the full pattern, and also the full semantics, of information realization explicit, but also providing the possibility to use it in a more conveneint way through the simple pattern. Whether that is a good choice will need further discussion, though.