context: It is probably the case that Julius is a lion. It is probable that Lily is a swan. It is probable that John dropped the milk.
hypothesis: Chances are about even that lily is a swan, and John dropped the milk.
valid_hypothesis: Chances are about even that lily is a swan, and John dropped the milk.
invalid_hypothesis: It is highly unlikely that lily is a swan, and John dropped the milk.
hypothesis_assertion: Lily is a swan, and John dropped the milk.