ABSTRACT
This chapter introduces the metaphysical framework within which my neo-Aristotelian theory of biological natural kind essentialism operates—an ontology of dispositional properties. The central conceptual features of these intrinsically powerful properties are discussed: their individuation via stimulus/manifestation conditions, their functional causal role and corresponding multiple realisability, and their teleological goal-directedness toward particular end-states. It is these features, this chapter argues, which uniquely qualify these properties to perform the role required of essence. After illustrating their suitability in this respect, the chapter identifies the most plausible place at which that role might be realised—the causal sub-systems whose capacities constitute the core developmental architecture in control of organismal morphology. In the process of examining the causal structure of these systems—especially their exhibition of robustness phenomena of persistence and plasticity through the lens of dynamical systems theory—the claim this chapter makes is that these dynamically directed generative mechanisms of ontogenesis are prime candidates to collectively constitute the neo-Aristotelian essences of biological natural kinds.
