Role Functions, Mechanisms, and Hierarchy

TLDR

Science advances by uncovering mechanisms and role functions, and Cummins' 1975 analysis defines a role function as a capacity of an item that appears in an analytic explanation of the capacity of a containing system, capturing a key sense of function in biology and beyond. Here I synthesize Cummins' account with recent work on mechanisms and causal/mechanical explanation. The synthesis yields an analysis of mechanistic role functions that incorporates the active, spatial, temporal, and hierarchical organization of mechanisms to refine Cummins' original proposal. The synthesis demonstrates that discovering a role function is a scientific achievement that contributes to interlevel integration of multilevel mechanisms and offers a unique, context‑specific variety of causal/mechanical explanation.

Abstract

Many areas of science develop by discovering mechanisms and role functions. Cummins' (1975) analysis of role functions—according to which an item's role function is a capacity of that item that appears in an analytic explanation of the capacity of some containing system—captures one important sense of “function” in the biological sciences and elsewhere. Here I synthesize Cummins' account with recent work on mechanisms and causal/mechanical explanation. The synthesis produces an analysis of specifically mechanistic role functions, one that uses the characteristic active, spatial, temporal, and hierarchical organization of mechanisms to add precision and content to Cummins' original suggestion. This synthesis also shows why the discovery of role functions is a scientific achievement. Discovering a role function (i) contributes to the interlevel integration of multilevel mechanisms, and (ii) provides a unique, contextual variety of causal/mechanical explanation.