context: We doubt that Julius is a swan. There is a very good chance that Sandra got the football. It is certain that Daniel dropped the milk. It is certain that if either Sandra got the football, or Daniel dropped the milk, then John left the football. It is probable that if Sandra got the football, or Julius is a swan, then Brian is a lion. Chances are slight that if Sandra got the football, and Julius is a swan, then Bernhard is a lion.
hypothesis: There is a better than even chance that sandra got the football, and Brian is a lion.
valid_hypothesis: There is a better than even chance that sandra got the football, and Brian is a lion.
invalid_hypothesis: It is improbable that sandra got the football, and Brian is a lion.
hypothesis_assertion: Sandra got the football, and Brian is a lion.