context: We believe that Daniel took the football. It is impossible that Mary put down the apple. Chances are slight that Julius is a lion. There is little chance that if Mary put down the apple, or Daniel took the football, then John dropped the apple. It is improbable that if either Mary put down the apple, or Daniel took the football, then Bernhard is yellow. We believe that if either Mary put down the apple, or Daniel took the football, then Sandra got the milk.
hypothesis: It is almost certain that either Sandra got the milk, or John dropped the apple.
valid_hypothesis: Chances are about even that either Sandra got the milk, or John dropped the apple.
invalid_hypothesis: It is almost certain that either Sandra got the milk, or John dropped the apple.
hypothesis_assertion: Either Sandra got the milk, or John dropped the apple.