Between Chance and Choice: A Layered Account of Stochasticity, Control, and Agency

The familiar dilemma says that a determined action is not free, while a random action is not controlled. That dilemma combines three different questions: whether nature is deterministic, whether an organism exercises causal control, and whether that control satisfies a philosophical or moral account of free will. This paper separates them. It develops a layered architecture in which an internal policy selects physical controls, those controls alter stochastic or deterministic transition laws, reachable pivotal states change action distributions, and outcomes are written into records used by later policies. Interventional contrasts, total-variation control capacity, data processing, and record use make the operational part testable. Stochastic slack may widen the support of possible outcomes, but it is neither sufficient nor necessary for operational agency. Steering is not an immaterial downward cause; it is the measured effect of a physically realized policy on lower-level dynamics. Readiness-potential experiments, neural noise, and threshold models constrain implementations but do not decide the metaphysics of free will. The same architecture admits a compatibilist reading under effective stochasticity and a libertarian extension if ontic indeterminism and an adequate sourcehood condition are independently established. Bioelectric or quantum mechanisms may instantiate a control channel, but neither label supplies agency by itself.