context: Chances are slight that Greg is a lion. It is probably not the case that Bernhard is a swan. It is probably not the case that Julius is green. It is unlikely that if Julius is green, or Bernhard is a swan, then Brian is gray. There is little chance that if Julius is green, and Bernhard is a swan, then Mary went to the kitchen. There is little chance that if either Bernhard is a swan, or Greg is a lion, then Lily is a rhino.
hypothesis: It is impossible that either Bernhard is a swan, or Julius is green.
valid_hypothesis: Chances are about even that either Bernhard is a swan, or Julius is green.
invalid_hypothesis: It is impossible that either Bernhard is a swan, or Julius is green.
hypothesis_assertion: Either Bernhard is a swan, or Julius is green.