Relation sumo#less_than (sumo#quantity,sumo#quantity)
  type:  pm#binary_predicate_type  the class of predicates relating two items - its valence is two
  type:  pm#irreflexive_relation_type  r is irreflexive if r(?i,?i) holds for no value of ?i
  type:  pm#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
  type:  pm#type_of_relation_extended_to_quantities  relation that, when it is true on a sequence of arguments that are real_numbers, it is also true on a sequence of constant_quantites with those magnitudes in some unit of measure; for example, the less_than relation is extended to quantities; this means that for all pairs of quantities ?q1 and ?q2, [?q1,  sumo#less_than: ?q2] if and only if, for some numbers ?n1 and ?n2 and unit ?u, [q1 =  sumo#measure_fn(?n1,?u)], [q2 =  sumo#measure_fn(?n2,?u)] and [?n1, less_than: ?n2] for all units on which ?q1 and ?q2 can be measured; note that, when a relation_extended_to_quantities is extended from real_numbers to constant_quantities, the constant_quantities must be measured along the same physical dimension
  supertype:  pm#trichotomizing_relation_on_real_number (sumo#quantity,sumo#quantity)
     supertype:  pm#trichotomizing_relation (?,?)  this category only serves structuration purposes: it is instance of pm#trichotomizing_relation_type which is not instance of pm#class_of_inheritable_relation_type
        supertype:  pm#binary_relation_with_particular_mathematical_property (?,?)
           supertype:  pm#relation_with_particular_mathematical_property (*)
              supertype:  pm#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:  pm#relation__related_thing__relatedthing___related_with  type for any relation (unary, binary, ..., *-ary) and instance of pm#relation_type
  supertype:  pm#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:  pm#binary_relation_with_particular_mathematical_property (?,?)
  supertype:  pm#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:  pm#binary_relation_with_particular_mathematical_property (?,?)