context: There is a better than even chance that Greg is a frog. There is a very good chance that Mary went to the office. Chances are about even that Bill is in the school. There is almost no chance that if Greg is a frog, or Bill is in the school, then Bernhard is gray. Chances are about even that if either Mary went to the office, or Greg is a frog, then Brian is green. It is probably the case that if Mary went to the office, and Bill is in the school, then John discarded the milk.
hypothesis: It is certain that bill is in the school, and Mary went to the office.
valid_hypothesis: Chances are about even that bill is in the school, and Mary went to the office.
invalid_hypothesis: It is certain that bill is in the school, and Mary went to the office.
hypothesis_assertion: Bill is in the school, and Mary went to the office.