context: We believe that John went to the hallway. It is impossible that Greg is a frog. There is little chance that Gertrude is a wolf. Chances are about even that if Gertrude is a wolf, or John went to the hallway, then Julie is in the kitchen. There is little chance that if either Gertrude is a wolf, or John went to the hallway, then Brian is a rhino. It is almost certain that if John went to the hallway, and Gertrude is a wolf, then Lily is white.
hypothesis: It is impossible that john went to the hallway, and Greg is a frog.
valid_hypothesis: It is impossible that john went to the hallway, and Greg is a frog.
invalid_hypothesis: There is a better than even chance that john went to the hallway, and Greg is a frog.
hypothesis_assertion: John went to the hallway, and Greg is a frog.