context: It is highly unlikely that Bernhard is a rhino. Chances are slight that Lily is green. Chances are about even that Fred is in the park. It is impossible that if Lily is green, or Fred is in the park, then Julius is a lion. There is a very good chance that if either Fred is in the park, or Lily is green, then Brian is a frog. It is unlikely that if Lily is green, or Fred is in the park, then John went to the hallway.
hypothesis: Chances are about even that john went to the hallway, or Brian is a frog.
valid_hypothesis: Chances are about even that john went to the hallway, or Brian is a frog.
invalid_hypothesis: There is almost no chance that john went to the hallway, or Brian is a frog.
hypothesis_assertion: John went to the hallway, or Brian is a frog.