context: It is highly unlikely that Bernhard is a swan. Chances are slight that Brian is gray. Chances are about even that Mary dropped the milk. It is almost certain that if either Mary dropped the milk, or Brian is gray, then John put down the apple. It is probably not the case that if Mary dropped the milk, or Brian is gray, then Sandra left the milk. It is certain that if Brian is gray, or Bernhard is a swan, then Greg is gray.
hypothesis: Chances are about even that either Sandra left the milk, or Mary dropped the milk.
valid_hypothesis: Chances are about even that either Sandra left the milk, or Mary dropped the milk.
invalid_hypothesis: It is almost certain that either Sandra left the milk, or Mary dropped the milk.
hypothesis_assertion: Either Sandra left the milk, or Mary dropped the milk.