context: It is impossible that Brian is a lion. There is almost no chance that John picked up the apple. It is highly unlikely that Winona is a wolf. Chances are about even that if either John picked up the apple, or Winona is a wolf, then Julius is a swan. It is probable that if Winona is a wolf, or John picked up the apple, then Mary is in the park. It is highly unlikely that if either Brian is a lion, or Winona is a wolf, then Fred went to the hallway.
hypothesis: It is certain that julius is a swan, and Mary is in the park.
valid_hypothesis: There is almost no chance that julius is a swan, and Mary is in the park.
invalid_hypothesis: It is certain that julius is a swan, and Mary is in the park.
hypothesis_assertion: Julius is a swan, and Mary is in the park.