Conventional framing
Causation is commonly understood as a relation in which one event or component produces another through a linear chain of interactions. In biology, this is often expressed in mechanistic terms, where parts are assigned causal roles based on their contribution to specific outcomes. Explanations are typically constructed by identifying discrete causes operating at a particular level, such as genes, molecular interactions, or environmental factors.
APS reframing
In APS, causation is not a linear relation between isolated events or components, but an organisation-dependent relation among processes that contribute to the maintenance or transformation of a system’s persistence.
Causal relations arise within organised systems whose continued existence depends on the coordinated activity of multiple processes. A process is causally relevant insofar as it contributes to sustaining or modifying the organisation that enables the system to persist. Causation is therefore not defined independently of organisation, but is constituted by it.
This shifts the focus from component-level interactions to constraint-based organisation. Biological systems persist by maintaining networks of constraints that channel processes in ways that sustain their continued existence. Causal relations are expressed through these constraints: processes matter not simply because they occur, but because of how they are organised and how they contribute to maintaining viable conditions.
Causation is intrinsically linked to persistence and viability. Persistence names the ongoing activity through which organisation is maintained, while viability specifies the conditions under which this activity can be sustained. Causal processes are those that contribute to maintaining or altering these conditions.
Causation in biological systems is therefore inherently multiscale. Processes at different scales—molecular, cellular, organismal, and ecological—are reciprocally related through the organisation of the system. No single level has absolute explanatory priority; causal significance depends on how processes are integrated within the organisation as a whole.
This account differs from reductionist approaches that seek to locate causation at a single privileged level, as well as from simple “top-down” or “bottom-up” models. Instead, causation is distributed across the organisation and depends on the coordinated interaction of processes across scales.
Understanding causation in this way allows biological explanation to move beyond the identification of isolated mechanisms toward the analysis of how organised systems maintain and transform themselves over time.
Key Point
Causation is not a linear relation between parts, but an organisation-dependent relation among processes that contribute to the persistence of a system.