#agent  an active and efficient cause; capable of producing a certain effect; "their research uncovered new disease agents"
  subtype:  #vasoconstrictor  #eliminator  #impairer  #mutagen  #quickener  #relaxer  #repressor  #satisfier  #shortener  #stressor  #teratogen  #vector.agent  #weakener
  supertype:  #causal_agent__cause__causal_agency  any entity that causes events to happen
     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

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