Relation rst#contrast (description_content/medium/container,description_content/medium/container)  comparability and differences of two situations
  exclusion:  circumstance  solution  elaboration  cause  effect  definition  comparison  means  condition  otherwise  interpretation  restatement  summary  theme
  supertype:  subject_matter_rhetorical_relation  symmetric_rhetorical_relation
  subtype:  antithesis (description_content/medium/container,description_content/medium/container)