context: It is almost certain that John picked up the milk. Chances are about even that Mary went to the kitchen. We believe that Greg is a frog. It is probably the case that if either Mary went to the kitchen, or John picked up the milk, then Brian is a rhino. It is highly unlikely that if Mary went to the kitchen, or Greg is a frog, then Bernhard is a rhino. It is almost certain that if Greg is a frog, and Mary went to the kitchen, then Sandra got the apple.
hypothesis: We believe that brian is a rhino, and Mary went to the kitchen.
valid_hypothesis: There is almost no chance that brian is a rhino, and Mary went to the kitchen.
invalid_hypothesis: We believe that brian is a rhino, and Mary went to the kitchen.
hypothesis_assertion: Brian is a rhino, and Mary went to the kitchen.