  It is less clear that Landauer himself thought he was introducing a new principle. It seems more plausible that he was taking for granted the Gibbsian approach to statistical mechanics, which identified p ln p as the statistical mechanical entropy long before Shannon's work, and the non-decrease of this entropy through coarse-graining. As such, the validity of Landauer's principle would still require the structure of Gibbsian statistical mechanics to be self-consistent and the appropriate representation of thermal systems. At the very least this cannot be taken for granted unless it has already been established that untamed demons do not exist and so the unquestioned use of Landauer's principle in exorcisms of the demon would still appear to be circular.