context: We doubt that Brian is a swan. It is highly likely that Lily is green. It is highly unlikely that Greg is gray. It is highly unlikely that if Greg is gray, or Brian is a swan, then John moved to the garden. Chances are about even that if Greg is gray, and Brian is a swan, then Mary grabbed the milk. There is almost no chance that if either Brian is a swan, or Greg is gray, then Julius is a frog.
hypothesis: It is almost certain that julius is a frog, and Lily is green.
valid_hypothesis: It is impossible that julius is a frog, and Lily is green.
invalid_hypothesis: It is almost certain that julius is a frog, and Lily is green.
hypothesis_assertion: Julius is a frog, and Lily is green.