context: There is almost no chance that Brian is a swan. It is probably not the case that Julius is white. It is unlikely that Lily is a lion.
hypothesis: It is impossible that brian is a swan, and Julius is white.
valid_hypothesis: It is impossible that brian is a swan, and Julius is white.
invalid_hypothesis: It is certain that brian is a swan, and Julius is white.
hypothesis_assertion: Brian is a swan, and Julius is white.