theorem instSpatiotemporalRegionAtToParent
theorem instSpatiotemporalRegionAtToParent: ∀ (x t : Type) [SpatiotemporalRegion.At x t], Occurrent.At x t
theorem instSpatiotemporalRegionAtToParent
theorem instSpatiotemporalRegionAtToParent: ∀ (x t : Type) [SpatiotemporalRegion.At x t], Occurrent.At x t