Relation pm#implication__then___therefore__therefore (description,description)
  supertype:  contextualizing_logical_relation__contextualizinglogicalrelation
  subtype:  equivalence__equivalentTo___iff__iff (description,description)
  subtype:  entails__entail (formula,formula)  the second argument is logically entailed from the first by means of the proof theory of SUO-KIF