 In instant-based models the primitive temporal entities are points in time, viz. time instants, and the basic relationship between them (besides equality) is temporal precedence. Thus, the flow of time is represented by a non-empty set of time instants \(T\) with a binary relation \(\prec\) of precedence on it: \(\mathcal{T} = \left\langle T, \prec \right\rangle.\)