What we discern is the specific character of a place through a period of time.

This is what I mean by an 'event.' We discern some specific character of an event.

But in discerning an event we are also aware of its significance as a relatum in the structure of events.

This structure of events is the complex of events as related by the two relations of extension and cogredience.

The most simple expression of the properties of this structure are to be found in our spatial and temporal relations.