According to Kuhlmann & Glennan, fundamental physics and New Mechanicism do “not fit well together” (Kuhlmann and Glennan, Euro J Phil Sci 4:338, 2014). For two main reasons: (1) Quantum mechanics (QM) challenges the hypothesis that there are objects with definite properties that are related by local causal interactions; (2) since mechanisms are composed of lower-lever mechanisms, then if in fundamental physics the existence of mechanisms can be questioned, and if macroscopic mechanisms supervene on fundamental physics entities and processes, then fundamental physics can even undermine mechanistic ontology and its explanatory ambition.
In their paper, Kuhlmann & Glennan tried to argue that the problem of the compatibilisation between fundamental physics and New Mechanicism can be partially addressed since, on the one hand, the quantum decoherence hypothesis allows to defend that the universal validity of quantum mechanics does not undermine New Mechanicism ontological and explanatory claims as they occur within in classical domains. And, on the other hand, it is possible to offer a non-classical mechanistic explanation of certain kinds of quantum phenomena.
This paper aims to argue that there has always been a problematic relationship between mechanical philosophy and fundamental physics throughout the history of physics. In fact, only for a short period of time could we say that fundamental physics has been compatible will mechanicism. Therefore, in part, the challenges posed by QM to mechanicism are not new. Nevertheless, mechanicism prevailed throughout the history of physics as an ideal ontology. On the other hand, I also aim to argue that although contemporary fundamental physics may not be compatible with New Mechanicism, that should not imply a rejection of mechanistic ontology for reasons other than the quantum decoherence hypothesis. That is, if Physics has not been playing a central role in the literature devoted to New Mechanical Philosophy that may not be simply a consequence of the hypothetical incompatibility between QM and Mechanicism ontology, but due to adhesion to a specific QM’s interpretation and the micro-physicalist assumption of the universal character of QM.