We discuss V.P. Belavkin’s approach to the measurement problem encapsulated in his theory of eventum mechanics (as presented in his 2007 survey). In particular, we show its relation to ideas based on superselection and interaction with the environment developed by N.P. Landsman (1995, and more recent papers). Landsman writes “those believing that the classical world exists intrinsically and absolutely [such persons later termed by him B-realists] are advised against reading this [his, 1995] paper”. He adopts a milder position, calling it that of an A-realist: we live in a classical world but to give it special status is like insisting that the Earth is the centre of the universe. The B-realists are accused of living under some kind of hallucination. Landsman presents arguments pointing in a particular direction to a resolution of the measurement problem which at least would satisfy the A-realists. We point out in this paper that the theory earlier developed by Belavkin (surveyed in his 2007 paper) seems to complete Landsman’s program or at least exhibits a “realisation” satisfying his desiderata. At the same time it seems that this completion of the program ends up giving both A- and B-realists equal licence to accuse the others of living under hallucinations. Preface This is a rough and still incomplete draft. It will come across to the reader as a private conversation between the author and his friends Slava Belavkin and Klaas Landsman. In particular, a proper introduction is urgently needed.