  A similar story applies to the distinction between mental events (John’s decision to wear boots) and physical or physiological events (such and such neurons firing). One may think that this distinction is real insofar as the latter events are expected to fall naturally into the nomological net of physical theories whereas the former seem to escape it. But one may also want to resist this line of thought and maintain that the distinction between the mental and the physical concerns exclusively the vocabulary with which we describe what goes on. These options have important ramifications for various issues in the philosophy of mind—e.g., issues of mental causation (Heil &amp; Mele 1993; Walter &amp; Heckmann 2003; Gibb et al. 2013). If the distinction between mental and physical events is ontologically significant, then the question arises of how these two sorts of event causally interact with each other, leading to various forms of anomalous or nomological dualism (Foster 1991). By contrast, the claim that the distinction is purely semantic is congenial to a monist position, whether nomological or anomalous (Macdonald 1989). Anomalous monism has been popular especially among philosophers who accept a particularist conception of events as widely redescribable entities, for such a conception allows one to accept the materialist claim that all events are physical (regardless of whether one describes them in mentalistic terms) while rejecting the seeming consequence that mental goings-on can be given purely physical explanations (precisely because only a physicalistic vocabulary is suited to such explanations) (Nagel 1965; Davidson 1970, 1993). Some authors, however, have argued that this line of argument falls prey to the charge of epiphenomenalism, to the effect that mental events would lack causal or explanatory powers altogether (Honderich 1982; Robinson 1982; Kim 1993; Campbell 1998, 2005) and on such matters the debate is still open.