In section 11.2 it was argued that our best physics suggests that there are relations other than spatiotemporal ones that do not supervene on the intrinsic properties of their relata. In this section it is argued that the principles of individuation for individual particles and spacetime points may involve relations and not intrinsic properties, and hence that physical individuals may be ‘relationally individuated’. In the next subsection, the debate about the identity and individuation of quantum particles is briefly explained. The following subsection concerns the notion of an individual, and the final subsection explains some recent work on the reduction of identity to different notions of discernibility in languages with different resources.
-  Note that monadic predicates can express relational rather than intrinsic properties and ourconcern is with the metaphysical difference between the latter not the syntactic matter of what kindsof predicates are used to refer to them.