sowa#relative_thing  Peirce/Sowa's notion of "secondness"; click here for details
  exclusion:  mediating_thing
  subtype:  prehension  proposition
  supertype:  thing_playing_some_role  category to classify things according to roles/viewpoints; classification under this category is application-dependant
     supertype:  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 relative_thing; click here to add one.