According to David Krakauer, complexity is the study of teleonomic matter; that is, matter with purpose. Teleological explanations are made in terms of goals and functions:
Teleology refers to a goal-oriented explanation, interpreting structures or dynamics in terms of their functions. In biological contexts, teleology is a consequence of natural selection, and in cultural contexts a result of learning and planning. Typically teleology implies internal states supporting conditional branching—pursuing different behaviors as a result of contingent history and context. @2024krakauer