Non-reductive physicalism and degrees of freedom

Non-reductive physicalism (NRP) consists of the following two theses: 1. All broadly scientific entities are nothing over and above physical entities1 (Physi-calism) 2. Some broadly scientific entities are ontologically irreducible to physical entities—i.e., are neither identical to any physical entities or states consisting of physical entities in purely physical relation, nor to any boolean or mereological combinations of such entities or states (Non-reduction) It has been claimed that NRP is not a stable position, on grounds that NRP either collapses into reductive physicalism (involving the denial of Non-reduction), or expands into emergentism of a robust or “strong ” variety (involving the denial of Physicalism).2 I will argue here that this claim is unfounded. NRP offers a viable middle ground between reductive physicalism and robust emergentism, according to which some phenomena are, as I’ll sometimes put it, ‘weakly emergent ’ from physical phenomena. ∗Thanks to audiences at Tufts University, the University of Kentucky, and the University of Toronto for helpful comments and questions. Special thanks to Benj Hellie and Jonathan McCoy for detailed feedback on previous versions, and to Robert Axtell, whose suggestion that reductions in degrees of freedom play a role in the physically unproblematic emergence of complex systems (made during the 2002 Case Studies of Emergence seminar series at the University of Michigan) inspired the present approach