context: It is highly unlikely that John got the apple. It is almost certain that Greg is a swan. It is improbable that Brian is a frog. There is almost no chance that if Brian is a frog, and John got the apple, then Mary grabbed the milk. It is unlikely that if either Greg is a swan, or Brian is a frog, then Fred left the football. Chances are slight that if Greg is a swan, and John got the apple, then Julius is a lion.
hypothesis: It is almost certain that either Greg is a swan, or Julius is a lion.
valid_hypothesis: It is almost certain that either Greg is a swan, or Julius is a lion.
invalid_hypothesis: We doubt that either Greg is a swan, or Julius is a lion.
hypothesis_assertion: Either Greg is a swan, or Julius is a lion.