ABSTRACT
According to the theory of biological natural kind essentialism, there exist of shared sets of properties among discrete groups of organisms which constitute generative capacities for particularised morphological development. However, philosophers have long agreed that the empirical evidence strongly suggests that no such sets exist. This widespread agreement is often not simply characterised negatively, as being based on the mere lack of aforementioned evidence, but positively, as a necessary corollary of evolutionary theory: the process of evolution via natural selection requires the constant changing of, and thus the inherent instability of, the collective properties possessed by groups of organisms. By drawing out the theoretical implications of the previous chapters’ metaphysical framework of dispositional properties, this chapter provides a response to the ‘no such set’ objection. In showing that morphological and genotypic variation among the members of natural kinds pose no threat to a neo-Aristotelian theory of biological natural kind essentialism, the chapter more fully fleshes out the details of that theory to show that it possesses the conceptual resources to withstand the forces of contingency and instability which accompany the process of evolution.
