Querying and reasoning for Social Semantic software ⋆ Fran¸ cois Bry, Jakub Kotowski and Klara Weiand Institute for Informatics, University of Munich Oettingenstr. 67, 80538 M¨ unchen, Germany http://pms.ifi.lmu.de Abstract. This presentation outlines requirements for querying and reasoning in a Social Semantic software context. A unified approach which tightly connects the two technologies is sketched. Introduction. Social Semantic software, for example Semantik Wikis, combines collaborative work and social interaction between users with Semantic Web tech- nologies. Reasoning, seen as the generation of new data from declarative speci- fications, and querying, seen as high-level and declarative access and data con- struction, are distinguishing features of Semantic software. In order to benefit non-expert users of social software, both technologies should be easy to use while at the same time providing expressive power to advanced users. Additionally, they should be fit to handle the conditions specific to Social Semantic software, such as social interaction, inconsistency arising from opposing viewpoints and work in progress, and the presence of both data and metadata. Querying. A query language for Social Semantic software should enable users to select, access and reuse data while at the same time being easy to use. A good query paradigm for such a language is declarative and logic-based, but simpler query languages are deemed neccessary to bridge the gap between simple full text search and powerful expert query languages. Several keyword query language for structured data have been proposed [2]. In addition, a query language for Social Semantic software should fulfill the following criteria: – Queries can be of varying complexity according to the users’ knowledge and information needs, meaning that users can simply enter some keywords and get meaningful related results, while more experienced users can create more specific, complex queries. The transition between the two is smooth and flexible. – All elements the user interacts with, such as textual content and its structure and tags and tag hierarchies are amenable to querying and it is possible to combine selection criteria for several data sources in one query. ⋆ The research leading to these results is part of the project “KiWi - Knowledge in a Wiki” and has received funding from the European Community’s Seventh Framework Programme (FP7/2007-2013) under grant agreement No. 211932.