context: There is a better than even chance that Greg is a rhino. There is little chance that Bernhard is a swan. Chances are about even that Brian is white. There is little chance that if either Greg is a rhino, or Brian is white, then Sandra left the milk. There is a very good chance that if Bernhard is a swan, or Greg is a rhino, then Lily is gray. It is certain that if Bernhard is a swan, and Brian is white, then Mary went to the garden.
hypothesis: Chances are about even that either Brian is white, or Sandra left the milk.
valid_hypothesis: Chances are about even that either Brian is white, or Sandra left the milk.
invalid_hypothesis: It is highly unlikely that either Brian is white, or Sandra left the milk.
hypothesis_assertion: Either Brian is white, or Sandra left the milk.