context: It is probably not the case that Julius is a swan. Chances are about even that John left the apple. There is a very good chance that Bernhard is gray. It is improbable that if either Bernhard is gray, or John left the apple, then Fred is in the bedroom. Chances are slight that if John left the apple, or Julius is a swan, then Mary went to the office. It is certain that if Julius is a swan, and John left the apple, then Brian is yellow.
hypothesis: We believe that brian is yellow, and Fred is in the bedroom.
valid_hypothesis: It is impossible that brian is yellow, and Fred is in the bedroom.
invalid_hypothesis: We believe that brian is yellow, and Fred is in the bedroom.
hypothesis_assertion: Brian is yellow, and Fred is in the bedroom.