ThepromiseoftheSemanticWeb atits most expansive is to allow knowledge to be freely accessed
and exchanged by software. It is now recognized that if the SemanticWebis to
containdeepknowledge theneedfornewrepresentationand reasoning techniques is going to be
critical. These techniques need to ?nd the righttrade-o?betweenexpressiveness
scalabilityandrobustnesstodealwiththe inherently incomplete contradictory and uncertain nature
of knowledge on the Web. The International Conference on Web Reasoning and Rule Systems (RR)
was founded to address these needs and has grown into a major international forum in this area.
The third RR conference was held during October 25-26 2009 in Chantilly Virginia co-located
with the International Semantic Web Conference (ISWC 2009). This year 41 papers were submitted
from authors in 21 countries. The P- gram Committee performed outstandingly to ensure that each
paper submitted to RR 2009 was thoroughly reviewed by at least three referees in a short - riod
of time. The resulting conference presented papers of high quality on many of the key issues
for reasoning on the Semantic Web. RR 2009 was fortunate to have two distinguished invited
speakers. Robert Kowalski in his talk - tegrating Logic Programming and Production Systems
with Abductive Logic Programming Agents addressed some of the fundamental considerations - hind
reasoning about evolving systems. Benjamin Grossof's talk SILK: Higher Level Rules with
Defaults and Semantic Scalability described the design of a major next-generation rule system.
The invited tutorial Uncertainty Reas- ing for the Semantic Web by Thomas Lukasiewicz provided
perspectives on a central issue in this area.
