context: It is likely that Fred went to the hallway. We believe that Sandra took the apple. It is unlikely that Emily is a cat.
hypothesis: Chances are about even that fred went to the hallway, and Sandra took the apple.
valid_hypothesis: Chances are about even that fred went to the hallway, and Sandra took the apple.
invalid_hypothesis: It is almost certain that fred went to the hallway, and Sandra took the apple.
hypothesis_assertion: Fred went to the hallway, and Sandra took the apple.