context: It is impossible that Greg is a rhino. It is improbable that Bernhard is a swan. There is little chance that John went to the hallway. It is probable that if John went to the hallway, or Greg is a rhino, then Brian is a lion. It is improbable that if either John went to the hallway, or Greg is a rhino, then Lily is white. It is highly likely that if either Bernhard is a swan, or Greg is a rhino, then Sandra got the apple.
hypothesis: It is certain that either Sandra got the apple, or Brian is a lion.
valid_hypothesis: Chances are slight that either Sandra got the apple, or Brian is a lion.
invalid_hypothesis: It is certain that either Sandra got the apple, or Brian is a lion.
hypothesis_assertion: Either Sandra got the apple, or Brian is a lion.