#rational_number  an integer or a fraction
  subtype:  #fraction  the quotient of two rational numbers
  supertype:  #real_number__real  any rational or irrational number
     supertype:  #complex_number__complexnumber__complex_quantity__complexquantity__imaginary_number__imaginarynumber  a number of the form a+bi where a and b are real numbers and i is the square root of -1
        supertype:  #number  a concept of quantity derived from zero and units; "every number has a unique position in the sequence"
           supertype:  #definite_quantity  a specific measure of amount
              supertype:  #measure__quantity__amount__quantum  how much there is of something that you can measure
                 supertype:  pm#attribute_or_quality_or_measure  e.g., mass, mass unit, 1 kg, frequency, [2-3] hz, color, blue, speed, 1 m/s
                    supertype:  pm#non_spatial_object__nonspatialobject  abstraction or description content/medium/container (a description medium that has some spatial feature is both instance of sumo#object and pm#non_spatial_object
                       supertype:  pm#entity  something that can be "involved" in a situation
                          supertype:  pm#thing__something___T__t___3D_or_4D_thing_or_anything_else  any category (type or individual) is instance of this type; any type is also a subtype of this type
                       supertype:  cyc#intangible  The collection of things that are not physical -- are not made of, or encoded in, matter. Every cyc#Collection is a cyc#intangible (even if its instances are tangible), and so are some cyc#individuals.  Caution: do not confuse `tangibility' with `perceivability' -- humans can perceive light even though it's intangible--at least in a sense.
                          supertype:  cyc#partially_intangible__partiallyintangible  The collection of things that either are wholly intangible (see cyc#Intangible) or have at least one intangible (i.e. immaterial) part (see cyc#intangibleParts). This includes intangible individuals, such as instances of cyc#Number-General  or cyc#Agreement, as well as non-individuals (all of which are intangible), i.e. instances of cyc#SetOrCollection.  It also includes things that have both tangible and intangible components (see cyc#CompositeTangibleAndIntangibleObject),  such as a printed copy of a newspaper (as its information content is intangible) or a person (as her mental states are intangible).
                             supertype:  pm#thing__something___T__t___3D_or_4D_thing_or_anything_else  any category (type or individual) is instance of this type; any type is also a subtype of this type
                    supertype:  pm#thing_that_can_be_seen_as_a_relation  usable as relation type
                       supertype:  pm#thing_playing_some_role  category to classify things according to roles/viewpoints; classification under this category is application-dependant
                          supertype:  pm#thing__something___T__t___3D_or_4D_thing_or_anything_else  any category (type or individual) is instance of this type; any type is also a subtype of this type
                    supertype:  pm#individual__particular___supertype_of_1st_order_types  all individuals (for concepts or relations) are implicitely or explicitely instance of that type
                       supertype:  pm#thing__something___T__t___3D_or_4D_thing_or_anything_else  any category (type or individual) is instance of this type; any type is also a subtype of this type

No statement uses or specializes #rational_number; click here to add one.