The paper proposes a process-based model for an ontology that encompasses the emergence of process systems generated by increasingly complex levels of organization. Starting with a division of processes into those that are persistent and those that are fleeting, the model builds through a series of exclusive and exhaustive disjunctions. The crucial distinction is between those persistent and cohesive systems that are energy wells, and those that are far-from-equilibrium. The latter are necessarily open; they can persist only by interaction with their environments. Further distinctions, developed by means of the notions of self-maintenance and error detection, lead to the identification of complex biological organisms that are flexible learners, some of which are self-conscious and form themselves into social institutions. This model provides a non-reductive model for understanding human beings as both embodied and yet emergent. In particular, it provides a way of characterizing action as ‘metaphysically deep’, not an ontological embarrassment within an otherwise physicalist world.