context: It is highly likely that Bill left the milk. There is a better than even chance that John went to the garden. Chances are about even that Greg is gray. It is probable that if Bill left the milk, or Greg is gray, then Lily is a rhino. It is highly unlikely that if Greg is gray, and Bill left the milk, then Bernhard is a swan. Chances are slight that if Greg is gray, and John went to the garden, then Brian is a frog.
hypothesis: It is certain that bill left the milk, and Greg is gray.
valid_hypothesis: Chances are about even that bill left the milk, and Greg is gray.
invalid_hypothesis: It is certain that bill left the milk, and Greg is gray.
hypothesis_assertion: Bill left the milk, and Greg is gray.