  Dynamics, the study of change, is normally the subject of mechanics. Whether
the chosen mechanics is ``fundamental'' and deterministic or
``phenomenological'' and stochastic, all changes are described relative to an
external time. Here we show that once we define what we are talking about,
namely, the system, its states and a criterion to distinguish among them, there
is a single, unique, and natural dynamical law for irreversible processes that
is compatible with the principle of maximum entropy. In this alternative
dynamics changes are described relative to an internal, ``intrinsic'' time
which is a derived, statistical concept defined and measured by change itself.
Time is quantified change.
