context: It is probably the case that Bernhard is a swan. It is impossible that Brian is a swan. We believe that Julius is a frog.
hypothesis: It is probable that brian is a swan, and Bernhard is a swan.
valid_hypothesis: It is impossible that brian is a swan, and Bernhard is a swan.
invalid_hypothesis: It is probable that brian is a swan, and Bernhard is a swan.
hypothesis_assertion: Brian is a swan, and Bernhard is a swan.