- From: Peter F. Patel-Schneider <pfps@research.bell-labs.com>
- Date: Thu, 07 Feb 2002 14:45:45 -0500
- To: heflin@cse.lehigh.edu
- Cc: www-webont-wg@w3.org
Hi: I have a bunch of comments on the Web Ontology Requirements document (Feb 7). There are a lot of places where the wording needs to be changed. I have carefully gone over the first section and have noted the worst problems in other sections, but there are lots more places where the wording is not correct. The document suffers from a serious case of self-importance. In particular, The Web Ontology language will be a significant advance in Web functionality and take interoperability beyond the present stage. pegged my hype-meter. I think that we should be very careful to not make such statements, particularly in a requirements document. The document still reads as if it was the separate creation of different people. The style should be at least a bit more uniform between the various use cases subsections. The order of the design goals is rather strange. In particular, I would think that it would be better to move 3.4 before 3.3 The document uses words with technical meaning in places where the technical meaning may not be what is wanted. In particular, unless ``resource'' means what it means in RDF I think that it should be avoided. So Ontologies must be resources with their own unique identifiers. can easily be read as implying that ontologies must be objects just like regular objects. The document anticipates some technical features of OWL. In particular, it uses URI as the term identification mechanism. This brings up the URI vs QName discussion. There are a number of places where the document places very strong requirements on OWL. In particular it states The language *must* allow properties to be associated with statements. I don't see this requirement on our ``A'' list. There are other very strong requirements in the document, including the closed-world requirement. This placing of requirements on OWL continues even into the Objectives section, where it says At a minimum, the language should recommend to users how they can specify their own default mechanisms. The beginning of Section 5 goes even further, and calls the requirements in Section 4 ``minimal [...] features''. This seems to be setting the WG up to fail big-time if even one of the requirements in Section 4 is not totally solved by OWL. The lexical representations requirement seems to be arguing that URIs have to have multiple lexical forms. I don't think that this is what was wanted here. Many of the requirements and objectives are not very well specified. In particular, what does it mean to support the use of variables in ontology definitions. Some of the objectives go beyond a web ontology language. For example, I view speech acts and conditions outside of a web ontology language if there is any semantics attached to their constructs. Here are some specific wording changes: It shall provide ... The language shall provide ... for such a language. to support these g & r. [use cases are not really *for* a language] i.e. the objectives i.e., the objectives and which tasks support it. and which tasks require it. [tasks don't support design goals---maybe you could change to support the inclusion of] of standard vocabularly terms of standard terms [it might be better to keep away from anything with a natural language tone to it] This notion of ontologies comes from Artificial Intelligence, [I don't think that this is really true, and in any case, I don't what to ghettoize this view of ontologies] terms in an ontology are not just defined in some natural language, they also have logical definitions [Again, I would stay away from NL. Also, the terms in a WebOnt ontology won't be defined in NL.] and attributes defined by DTDs or XML Schemas do not have any semantics associated with them; [This is a very strong statement. It might be fine for an opinion piece, but do we really want to get all the XML people even madder with us?] In RDF Schema, you can RDF Schema can [I would stay away from the use of second-person.] and you can define properties and can define properties richer semantics are needed. [statements like this need some justification] One of the goals of this document is to specify exactly what is needed by a Web Ontology language [I thought that this was an initial list, not the final one.] There are numerous uses for ontologies on the Web. [This should, if included, be in the first section.] be the be that large corporations massive large corporation's [is massive really needed here] Language neutral representation Language-neutral representation changing any axioms, thus determining backwards-compatibility requires more than a simple comparison of axioms. [This assumes that an ontology will contain axioms.] low-learning barrier low learning barrier an reused and reused
Received on Thursday, 7 February 2002 14:47:48 UTC