A Subjectivist Interpretation of Relevant Information

A frequent complaint about current theories of information is that they are utterly useless when it comes to establish the actual relevance of some specific piece of information. As a rule, agents assume that some content is by default an instance of information (Sperber and Wilson [1995]). What they often wonder is whether and how far that content may contribute to the formulation of their choices and purposes, the development of their decision processes and eventually the successful pursuit of their goals. In light of this problem, this paper pursues two goals. The first is to provide a subjectivist interpretation of epistemic relevance (i.e. epistemically relevant semantic information, more on this presently), thus satisfying those critics who lament its absence and, because of it, may be skeptical about the utility of using information-theoretical concepts to tackle conceptual problems and cognitive issues in real life. The second goal is to show that such a subjectivist interpretation can (indeed must) be built on a veridical conception of semantic information, thus vindicating a strongly semantic theory of information (Floridi [2004b]) and proving wrong those critics who argue that misinformation can be relevant.