Formalizing belief reports: the approach and a case study

One of the most interesting puzzles in formalizing belief contexts is the fact that many belief reports can be given both an opaque and a transparent readings. A traditional explanation is that the two readings are related to the failure and success of the principle of substitutivity respectively, and this in turn is explained with the de re/de dicto distinction. We propose an alternative analysis, based on the idea that another agent's beliefs can just be quoted (preserving opacity) or translated into the reporter's language (allowing for transparency). We show that MultiContext systems allow for the formalization of these two phenomena at the same time, thanks to their multi-language feature.