context: It is impossible that Julius is gray. It is probably the case that Greg is a rhino. It is highly likely that Brian is green. Chances are about even that if Brian is green, and Greg is a rhino, then John put down the milk. We doubt that if Julius is gray, or Greg is a rhino, then Mary went to the hallway. It is highly unlikely that if either Julius is gray, or Greg is a rhino, then Lily is a frog.
hypothesis: We believe that lily is a frog, and Brian is green.
valid_hypothesis: There is almost no chance that lily is a frog, and Brian is green.
invalid_hypothesis: We believe that lily is a frog, and Brian is green.
hypothesis_assertion: Lily is a frog, and Brian is green.