context: It is probable that Julius is a rhino. It is unlikely that Mary dropped the milk. There is a very good chance that Brian is a lion.
hypothesis: Chances are about even that either Brian is a lion, or Julius is a rhino.
valid_hypothesis: Chances are about even that either Brian is a lion, or Julius is a rhino.
invalid_hypothesis: It is certain that either Brian is a lion, or Julius is a rhino.
hypothesis_assertion: Either Brian is a lion, or Julius is a rhino.