, Volume 69, Issue 1, pp 69–92 | Cite as

Understanding Epistemic Relevance

  • Luciano Floridi
Original Paper


Agents require a constant flow, and a high level of processing, of relevant semantic information, in order to interact successfully among themselves and with the environment in which they are embedded. Standard theories of information, however, are silent on the nature of epistemic relevance. In this paper, a subjectivist interpretation of epistemic relevance is developed and defended. It is based on a counterfactual and metatheoretical analysis of the degree of relevance of some semantic information i to an informee/agent a, as a function of the accuracy of i understood as an answer to a query q, given the probability that q might be asked by a. This interpretation of epistemic relevance vindicates a strongly semantic theory of information, according to which semantic information encapsulates truth. It accounts satisfactorily for several important applications and interpretations of the concept of relevant information in a variety of philosophical areas. And it interfaces successfully with current philosophical interpretations of causal and logical relevance.


Relevant Information Multiagent System Semantic Information Artificial Agent Subjectivist Interpretation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



The first time I discussed the topic of a theory of epistemic relevance was during a talk I gave at the University of Regensburg (Regensburg, Germany 9 November 2005). I owe to Rainer Hammwoehner and Hans Rott not only the kind invitation but also the conceptual pressure that made me start working on this paper. A first version of the paper was then presented at the Department of Communication Science of the University of Salerno (Fisciano, Italy, 10 May 2006), and I wish to thank Roberto Cordeschi for that opportunity and the feedback I received in that occasion. The paper was further improved and discussed at the “Workshop on Information Theories”, organized by Juerg Kohlas and Giovanni Sommaruga at Fribourg University (Münchenwiler, Switzerland, 17–18 May 2006). They, the attendees, and especially Rolf Haenni and Jeremy Seligman provided some very helpful comments. A new version was the subject of an invited talk at the Department of Philosophy of the University of Siena (Siena, 14 June 2006), where I took advantage of a long discussion with Claudio Pizzi on secondorder probabilities. This led to a paper presented at a seminar organised by the Computer Science Department of Mälardalen University (Västerås, Sweden, September 2006), where I was kindly invited by Gordana Dodig Crnkovic. The discussion with the participants and especially with Gordana, Susan Stuart and Lars-Göran Johansson generated several improvements. The issue of hardwired questions was discussed there. The final version of the article then became the ISI Samuel Lazerow Memorial Lecture I delivered at the University of Arizona (Tucson, 8 February 2007). I am grateful to Don Fallis for the invitation and to the Research Group on the History and Philosophy of Information Access, the School of Information Resources and Library Science and The International Visitors Fund for the kind support. The last opportunity I had to discuss this paper was as an invited lecture at the 30th Wittgenstein Symposium and at the 48th Boston Colloquium for Philosophy of Science. Finally, I would like to acknowledge the help, useful comments and criticisms by Pia Borlund, Ken Herold, Karen Mather, Paul Oldfield and Federica Russo and the journal’s anonymous referees. As usual, all the aforementioned people are responsible only for the improvements and not for any remaining mistakes.


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Copyright information

© Springer Science+Business Media B.V. 2007

Authors and Affiliations

  1. 1.Department of Philosophy, School of HumanitiesUniversity of HertfordshireHatfieldUK

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