According to Whitehead, the most primitive real unit is an actual occasion, which is not any thing or substance that persists in time, but a process, a process of becoming. This process of becoming is related to every other process of becoming, or as Whitehead’s commentators have explained, the basic unit of reality is a Leibnizian monad that has windows on every conceivable “surface.” The entire world is organic and “nature is a structure of evolving processes.” Reality is process. Moreover, Whitehead believed that his ontology, unlike the scientific ontology of inert objects, allowed for the existence of an evolving God.