theorem instSpatialRegionAtToParent
theorem instSpatialRegionAtToParent: ∀ (x t : Type) [SpatialRegion.At x t], ImmaterialEntity.At x t
theorem instSpatialRegionAtToParent
theorem instSpatialRegionAtToParent: ∀ (x t : Type) [SpatialRegion.At x t], ImmaterialEntity.At x t