LC Responses/MSM1

"Thanks for the good work", but:

HCLS IG has a few applications where rules are used in combination with OWL/RDF. In general, being able to build OWL out of RIF is an appealing form of interoperability. So, I have some concerns about the fact that in RIF the xsd numeric types have disjoint value spaces (as in XSD1.1, unlike current OWL 2 drafts). I am also concerned to learn that there are different data types in RIF versus OWL. For example, maybe OWL-RL could be implemented on top of RIF, but this could become impractical if there are data type issues. I hope that the data type issues between OWL and RIF can eventually be resolved.

BTW, it would be useful to have a short overview of the document set that briefly explains the content/purpose of each document.

PeterPatel-Schneider 23:14, 11 March 2009 (UTC)

[Draft Response for LC Comment 22:]

Dear Scott,

Thank you for your message <> on the OWL 2 Web Ontology Language last call drafts.

Thank you for your support of new features in OWL 2.

The OWL WG acknowledges that there are applications where one would like to use OWL and RIF. However, the needs of a representation language have driven the OWL WG to make certain choices regarding which datatypes are in OWL 2. The OWL WG has tried to support a large collection of datatypes, which may be larger than that supported by RIF. Applications that want to use both OWL and RIF can restrict themselves to those datatypes that are supported by both OWL and RIF.

The OWL WG had wanted to have a single base type for its numeric types, namely owl:realPlus. Several comments, yours included, have resulted in the OWL WG moving to align with XML Schema, and thus RIF, so that in OWL 2 xsd:decimal, xsd:float, and xsd:double now have pairwise disjoint value spaces. As a result of this change the need for owl:realPlus has disappeared and it has been removed from OWL 2. Several OWL 2 documents have been or are being modified to effect these changes.

The OWL WG has realized that an overview document would be useful and to that end has produced the Document Overview, with working draft available at

The typographical error that you point out in the New Features and Rationale document has been fixed.

Please acknowledge receipt of this email to <> (replying to this email should suffice). In your acknowledgment please let us know whether or not you are satisfied with the working group's response to your comment.

Regards, Peter F. Patel-Schneider on behalf of the W3C OWL Working Group

Last modified on 18 March 2009, at 18:21