context: We doubt that Mary took the milk. It is improbable that Greg is yellow. Chances are slight that Julius is a lion. There is a better than even chance that if Mary took the milk, or Julius is a lion, then Emily is a wolf. There is almost no chance that if Julius is a lion, and Mary took the milk, then Brian is white. It is probably not the case that if either Greg is yellow, or Julius is a lion, then John moved to the office.
hypothesis: It is highly unlikely that either Brian is white, or John moved to the office.
valid_hypothesis: It is highly unlikely that either Brian is white, or John moved to the office.
invalid_hypothesis: It is almost certain that either Brian is white, or John moved to the office.
hypothesis_assertion: Either Brian is white, or John moved to the office.