context: There is little chance that Lily is yellow. Chances are slight that Brian is a swan. Chances are about even that Greg is gray. It is improbable that if Greg is gray, or Brian is a swan, then John went to the office. It is improbable that if Greg is gray, and Brian is a swan, then Bernhard is a lion. It is impossible that if Lily is yellow, or Brian is a swan, then Sandra left the apple.
hypothesis: Chances are about even that either Greg is gray, or Sandra left the apple.
valid_hypothesis: Chances are about even that either Greg is gray, or Sandra left the apple.
invalid_hypothesis: It is impossible that either Greg is gray, or Sandra left the apple.
hypothesis_assertion: Either Greg is gray, or Sandra left the apple.