The very manner in which origination occurs—namely motion—and the fact that motion must have a cause, both indicate that such a cause has to be an actual, operative cause, for new states arise within it incessantly, one after another. Either it possesses an enduring essence whose states undergo alteration, or it does not. Were its states not subject to change, no change could proceed from it; yet were it not permanent and abiding, the continuity of that change could not be maintained. In all cases, change requires a lasting substratum, whether the change lies in the agent at the moment it acts or in the recipient while it is acted upon. Hence the objection under discussion falls away: the chain of causes invoked to explain contingent events ultimately terminates in primary causes whose essences remain fixed while their states alternate, and this alternation is the source of every fresh occurrence. Moreover, that stable essence—together with the state that issues from it by virtue of another factor—yields a further determinate condition through which the essence once again becomes the cause of the next thing to come into being.