APS places agency at the centre of biological explanation, but this emphasis can be misunderstood if agency is interpreted in psychological or intentional terms.
In APS, agency does not refer to intention, cognition, or conscious control. It refers to the viability-oriented organisation through which living systems actively sustain, regulate, and reproduce the conditions of their own persistence.
This emphasis is methodological rather than metaphysical. APS does not introduce agency as an additional component of biological systems; it identifies agency as the operational expression of constraint-closed organisation in action.
Biological explanation requires recognising that living systems are not passively shaped by external forces. They continuously modulate their internal and external conditions in ways that maintain their own organisation. This activity is what APS terms agency.
Key Point. APS emphasises agency because it makes explicit the activity through which living systems sustain themselves—an activity that must be presupposed by any account of evolution, function, or regulation.