context: It is impossible that Fred went to the hallway. It is probably the case that Brian is yellow. It is unlikely that Jessica is a cat. It is highly unlikely that if either Brian is yellow, or Fred went to the hallway, then Daniel left the football. We doubt that if Fred went to the hallway, and Jessica is a cat, then Gertrude is a wolf. Chances are slight that if Brian is yellow, or Fred went to the hallway, then John picked up the apple.
hypothesis: It is impossible that gertrude is a wolf, or Fred went to the hallway.
valid_hypothesis: It is impossible that gertrude is a wolf, or Fred went to the hallway.
invalid_hypothesis: Chances are about even that gertrude is a wolf, or Fred went to the hallway.
hypothesis_assertion: Gertrude is a wolf, or Fred went to the hallway.