Supervenience

In philosophy, supervenience is a dependency relation between two sets of properties: the subvenient properties (typically physical or lower-level) and the supervenient properties (typically mental, biological, or higher-level). The core idea is that there can be no difference in the supervenient properties without some difference in the subvenient properties. Mental states supervene on brain states: if two individuals are physically identical in every relevant respect, they cannot differ in their mental states.

Supervenience is often invoked as a way of capturing the dependence of higher-level phenomena on lower-level phenomena without committing to reductionism. It allows that mental properties are genuinely distinct from physical properties while insisting that they are not free-floating: they are anchored to the physical base.

The concept was introduced into philosophy of mind by Donald Davidson in 1970 and has since been applied to debates about the relationship between chemistry and physics, biology and chemistry, and social facts and individual behavior. In the context of emergence, supervenience captures the intuition that emergent properties are novel but not autonomous: they depend on their base without being reducible to it.