context: It is highly likely that Mary went to the hallway. It is impossible that Julius is a lion. It is probably the case that Brian is green. Chances are slight that if Brian is green, and Mary went to the hallway, then Jessica is a mouse. Chances are about even that if Mary went to the hallway, and Brian is green, then Lily is a swan. It is improbable that if either Julius is a lion, or Brian is green, then Fred dropped the apple.
hypothesis: It is almost certain that fred dropped the apple, and Julius is a lion.
valid_hypothesis: It is impossible that fred dropped the apple, and Julius is a lion.
invalid_hypothesis: It is almost certain that fred dropped the apple, and Julius is a lion.
hypothesis_assertion: Fred dropped the apple, and Julius is a lion.