context: It is almost certain that Julius is a swan. There is a very good chance that Bernhard is gray. It is unlikely that Brian is white. It is highly unlikely that if either Julius is a swan, or Brian is white, then Greg is green. Chances are about even that if either Brian is white, or Julius is a swan, then Lily is a rhino. It is impossible that if Julius is a swan, or Bernhard is gray, then Mary dropped the apple.
hypothesis: There is a very good chance that mary dropped the apple, or Bernhard is gray.
valid_hypothesis: There is a very good chance that mary dropped the apple, or Bernhard is gray.
invalid_hypothesis: We doubt that mary dropped the apple, or Bernhard is gray.
hypothesis_assertion: Mary dropped the apple, or Bernhard is gray.