context: Chances are about even that Mary went to the office. Chances are about even that Brian is white. It is likely that Julius is a swan. We believe that if Brian is white, and Julius is a swan, then Gertrude is a mouse. It is likely that if either Julius is a swan, or Brian is white, then Greg is a swan. It is certain that if Brian is white, or Mary went to the office, then Bernhard is yellow.
hypothesis: It is impossible that brian is white, or Julius is a swan.
valid_hypothesis: There is a very good chance that brian is white, or Julius is a swan.
invalid_hypothesis: It is impossible that brian is white, or Julius is a swan.
hypothesis_assertion: Brian is white, or Julius is a swan.