Relation sumo#proper_part__proper_part_of (object,object)  the 1st argument is part of the 2nd but is not it; this is a transitive_relation and asymmetric_relation (hence an irreflexive_relation)
  type:  asymmetric_relation_type  an antisymmetric and irreflexive relation
  type:  transitive_relation_type  a binary_relation ?REL is transitive if (?REL ?INST1 ?INST2) and (?REL ?INST2 ?INST3) imply (?REL ?INST1 ?INST3), for all ?INST1, ?INST2, and ?INST3
  supertype:  part__part_of (object,object)  this type should have been name sumo#part_of to respect the common reading conventions of parameters; all other mereological relations are defined in terms of this one; it means that the 1st argument is part of the 2nd; note that, since part is a reflexive_relation, every object is a part of itself
     supertype:  spatial_relation_from_entity_with_spatial_feature (object,*)
        supertype:  relation_from/to_thing_of_common_kind (*)  this type permits to categorize relations according to their signatures and hence offers (i) a concise way to set essential exclusion relations, and (ii) a systematic and easy-to-follow categorization
           >part of:  relation__related_thing__relatedthing___related_with  type for any relation (unary, binary, ..., *-ary) and instance of pm#relation_type
     supertype:  part_of (?,?)  this type SHOULD NOT BE USED IN WEBKB (its inverse may be used); this type is only provided for knowledge sharing purposes
        supertype:  mereological_relation (?,*)
           supertype:  relation_playing_a_special_role (*)  this type permits to categorize relations according to their roles ; this is a traditional but quite subjective way of categorizing relations
              >part of:  relation__related_thing__relatedthing___related_with  type for any relation (unary, binary, ..., *-ary) and instance of pm#relation_type
           supertype:  what_relation (*)
              supertype:  wh-/how_relation (*)  this type permits to categorize relations according to the usual who/what/why/where/when/how questions ; this is a traditional but very subjective and ineffective way of categorizing relations 
                 >part of:  relation__related_thing__relatedthing___related_with  type for any relation (unary, binary, ..., *-ary) and instance of pm#relation_type
  supertype:  asymmetric_relation (?,?)  this category only serves structuration purposes: it is instance of pm#asymmetric_relation_type which is not instance of pm#class_of_inheritable_relation_type
     supertype:  irreflexive_relation__irreflexiverelation (?,?)  this category only serves structuration purposes: it is instance of pm#irreflexive_relation_type which is not instance of pm#class_of_inheritable_relation_type
        supertype:  binary_relation_with_particular_mathematical_property (?,?)
           supertype:  relation_with_particular_mathematical_property (*)
              supertype:  relation_with_particular_property (*)  this rather fuzzy type permits to group categorization schemes less common than those covered by the previous sibling categories
                 >part of:  relation__related_thing__relatedthing___related_with  type for any relation (unary, binary, ..., *-ary) and instance of pm#relation_type
     supertype:  antisymmetric_relation__antisymmetricrelation (?,?)  this category only serves structuration purposes: it is instance of pm#antisymmetric_relation_type which is not instance of pm#class_of_inheritable_relation_type
        supertype:  binary_relation_with_particular_mathematical_property (?,?)
  supertype:  transitive_relation (?,?)  this category only serves structuration purposes: it is instance of pm#transitive_relation_type which is not instance of pm#class_of_inheritable_relation_type
     supertype:  binary_relation_with_particular_mathematical_property (?,?)