Abstract

There appear to be at least two kinds of compound physical substances: compound pieces of matter, which have their parts essentially, and living organisms, which do not. Examples of the former are carbon atoms, salt molecules, and pieces of gold; and examples of the latter are protozoa, trees, and cats. Given that there are compound entities of these two kinds, and given that they can be created or destroyed by assembly or disassembly, questions naturally arise about the nature of the causal relations which unite their parts. In answer to these questions, we first argue that the parts of a compound piece of matter are connected via a relation of dynamic equilibrium of attractive and repulsive forces. We then argue that the parts of an organic living thing are united in a different way: they are functionally connected in a broadly Aristotelian sense which is compatible with an ultimately non‐teleological, naturalistic biology.