ABSTRACT
This chapter presents the idea that the traditional account of an item's essential nature leaves out many of its significant properties. Then the idea that there are facts about communities, patterns to community structure and ways of describing biological systems in general which reveal communities to be more than inheritors of properties of their components. The notion of supervenience is widely used and discussed in the philosophy of mind and action, it is helpful, for the purposes, to consider simple kinds of supervenience. The existence of guilds poses interesting problems about the supervenience of ecological traits. The chapter preserves the distinction between the intrinsically functionless, autonomous natural creature, on the one hand, and the truth of the claim that some creatures do have an ecological, or community, function on the others. Ecological community is a commonplace of ecological folklore that biological communities and ecosystems are equilibrium aggregates of diverse species living in complex interrelationship with each other.
