Ontology of Representations

It’s been three days that I’m struggling with concepts of content, form, representation and so on.. I wonder whether there’s a well-formalized theory of representations out there.. the one in DOLCE is a useful design pattern, but I’m still reluctant to say that it is complete (I hope I’ll find out to be wrong). Another clever view of the issue can be found in a tutorial by Richiiro Mizoguchi, and this is what this post is about.

In this tutorial Mizoguchi talks about representationrepresented-thingrepresentational-form etc.. No mention of information-objects, which are instead (only as a term, maybe) always present everywhere else (Dolce, Cidoc, Cyc). So what’s the proper mapping? Is an IO a representation? Moreover, I am trying to put also another model in the picture, FRBR. This bibliographic standard focuses around concepts such as work, expression and manifestation, mainly. So how do these come into the game?

Sometimes I end up in some sort of ontological relativism. Since the objects we study are essentially multidimensional, and since we humans can only rationally perceive a portion of such dimensions at a given time, it follows that whatever perspective we decide to take on our objects of investigation, it will be fundamentally arbitrary and partial. In other words, there is no chance of having a single unifying perspective on reality, one which can contain all the others. No chance. So every representation gives you one side of the story only – which can be related to other sides, but never in its entirety.
If this is the case, we better keep all the possible ‘sides’ of this story, and just use the one we need whenever we need it. A pragmatist approach? Well.. more on this to come soon! (i’d also like to go back to Peirce, and check how all of this relates to his work)

Back to us: this is the model used in Dolce (more precisely, in the DnS module of Dolce, as described in Gangemi, A., Borgo, S., & Catenacci, C. (2005). Metokis deliverable D07 – Task Taxonomies for Knowledge Content. Deliverable of the EU FP6 project Metokis):

Dolce DnS

And this is an example of its instantiation:

Dolce DnS instantiation

The theory of Mizoguchi, as I said, it’s quite different. Here’s an interesting excerpt from the article Mizoguchi, R. (2004). Tutorial on ontological engineering – Part 3: Advanced course of ontological engineering. New Generation Computing, 22(2), 198–220.

A representation is composed of two parts, form and content.

…….p/o “form”: Representational form
…….p/o”content”: Proposition

where p/o stands for part-of relation/slot, “form” slot name and “: Representation” is a class constraint the slot value has to satisfy. Its identity is inherited from the form which is usually what people sense its existence. On the other hand, the content is the hidden part and it is a proposition which the author of the representation would like to convey through the representation.
It is critical to distinguish among proposition(content), representation and form of representation. In fact, although a novel is written in terms of sentences, novel is not a subclass of representation. What exists as a subclass of representation are what have the form of representation as its intrinsic property, that is, sentence, musical score, painting, etc. The sentences of Tale of Genji are instance-of sentence. However, representation and form of representation are different. Concerning a novel, representation is “sentence” which is composed of its content(novel) and “natural language” which is the syntactic part of the sentence, as the form of representation.

This is a quite impressive visual rendering of this ontological theory:

Mizoguchi representation ontology


How are these theories different from each other? What are their pros and cons, where is it that they could be used more successfully? There’s work to be done here..



2 Responses to “Ontology of Representations”

When you say DOLCE, you do mean the Information Objects module (OIO) right? Did you also take a look at the O² work, where they build a meta-ontology based on OIO? There’s a paper in the EON 2006, but also a longer TR on their own website.

Denny Vrandecic added these pithy words on Mar 08 07 at 1:15 pm

[…] I wrote something in the last weeks about the difficulties related to the modeling of representations and their contents. So today I just read this article by Stefano Mazzocchi, which basically hints at the same issue, but from an “RDF” perspective. It’s a very interesting article, so I just wanted to quote and comment a few  passages: The concept of data integration is even older than computers, it’s as old as the idea of data itself: all datasets that we use today, from a book to a collection of pictures, from a library catalog to census data, had to be collected by different people/entities and integrated. […]

Modeling Representations (take 2) at Mikele Pasin’s Weblog added these pithy words on Mar 30 07 at 12:32 pm