context: It is probably the case that Brian is green. We believe that Greg is a lion. It is probable that John went to the kitchen.
hypothesis: It is impossible that either John went to the kitchen, or Greg is a lion.
valid_hypothesis: Chances are about even that either John went to the kitchen, or Greg is a lion.
invalid_hypothesis: It is impossible that either John went to the kitchen, or Greg is a lion.
hypothesis_assertion: Either John went to the kitchen, or Greg is a lion.