术语信息
Comment: All instances of continuant [snap:Continuant] are spatial entities, that is, they enter in the relation of (spatial) location with spatial region [snap:SpatialRegion] entities. As a particular case, the exact spatial location of a spatial region [snap:SpatialRegion] is this region itself.
Definition: A continuant [snap:Continuant] that is neither bearer of quality [snap:Quality] entities nor inheres in any other entities.
Comment: An instance of spatial region [snap:SpatialRegion] is a part of space. All parts of space are spatial region [snap:SpatialRegion] entities and only spatial region [snap:SpatialRegion] entities are parts of space. Space is the entire extent of the spatial universe, a designated individual, which is thus itself a spatial region [snap:SpatialRegion].
Examples: the sum total of all space in the universe, parts of the sum total of all space in the universe
Comment: Space and spatial region [snap:SpatialRegion] entities are entities in their own rights which exist independently of any entities which can be located at them. This view of space is sometimes called "absolutist" or "the container view". In BFO, the class site [snap:Site] allows for a so-called relational view of space, that is to say, a view according to which spatiality is a matter of relative location between entities and not a matter of being tied to space. The bridge between these two views is secured through the fact that while instances of site [snap:Site] are not spatial region [snap:SpatialRegion] entities, they are nevertheless spatial entities.
BFO 2 Reference: Spatial regions do not participate in processes.
Spatial region doesn't have a closure axiom because the subclasses don't exhaust all possibilites. An example would be the union of a spatial point and a spatial line that doesn't overlap the point, or two spatial lines that intersect at a single point. In both cases the resultant spatial region is neither 0-dimensional, 1-dimensional, 2-dimensional, or 3-dimensional.
A spatial region is a continuant entity that is a continuant_part_of spaceR as defined relative to some frame R. (axiom label in BFO2 Reference: [035-001])
(forall (x) (if (SpatialRegion x) (Continuant x))) // axiom label in BFO2 CLIF: [035-001]
(forall (x y t) (if (and (SpatialRegion x) (continuantPartOfAt y x t)) (SpatialRegion y))) // axiom label in BFO2 CLIF: [036-001]
All continuant parts of spatial regions are spatial regions. (axiom label in BFO2 Reference: [036-001])