context: It is probably the case that Brian is gray. It is highly unlikely that John went to the hallway. It is probably the case that Bernhard is yellow. We doubt that if either Bernhard is yellow, or John went to the hallway, then Lily is a swan. There is a better than even chance that if Brian is gray, or Bernhard is yellow, then Greg is a rhino. It is highly unlikely that if John went to the hallway, and Brian is gray, then Julie is in the bedroom.
hypothesis: It is impossible that brian is gray, and Bernhard is yellow.
valid_hypothesis: Chances are about even that brian is gray, and Bernhard is yellow.
invalid_hypothesis: It is impossible that brian is gray, and Bernhard is yellow.
hypothesis_assertion: Brian is gray, and Bernhard is yellow.