context: Chances are about even that Bill put down the milk. It is probably not the case that Brian is a lion. It is probable that Mary moved to the office.
hypothesis: There is little chance that brian is a lion, and Bill put down the milk.
valid_hypothesis: There is little chance that brian is a lion, and Bill put down the milk.
invalid_hypothesis: It is certain that brian is a lion, and Bill put down the milk.
hypothesis_assertion: Brian is a lion, and Bill put down the milk.