A composed (mediated) relation used here to make relations 'temporary': by adding it as a superrelation, the effect is that the two related endurants cannot be present at all the same time intervals, but are compresent at least at some time interval (see related axiom).In FOL, the same constraint can be stated directly by coreference.This workaround can be used to index time of relations that involve reciprocal dependency, but it cannot be used in general with relations involving multiple strata of reality. For example, _about_ relation can be temporally indexed, without involving that the time of the information object overlaps with the time of the entity the information is about (but this works for e.g. the _realizes_ relation between information objects and entities whatsoever). The different temporal constraints of about vs. expresses probably derive from the dependency of aboutness from conception (to be about x, an information object should also express a description d that is satisfied by a situation including x, then temporal overlapping of _about_ is true in virtue of d). On the other hand, even conceives cannot be indexed in this way, because overlapping does not hold between the time og the conceiving agent, and the conceived description (or situation).