context: Chances are about even that Greg is a swan. It is unlikely that Gertrude is a mouse. Chances are about even that John picked up the apple. We doubt that if John picked up the apple, and Gertrude is a mouse, then Lily is white. It is almost certain that if Gertrude is a mouse, and Greg is a swan, then Mary moved to the office. There is a better than even chance that if either John picked up the apple, or Gertrude is a mouse, then Julius is green.
hypothesis: There is a very good chance that either John picked up the apple, or Julius is green.
valid_hypothesis: It is probably not the case that either John picked up the apple, or Julius is green.
invalid_hypothesis: There is a very good chance that either John picked up the apple, or Julius is green.
hypothesis_assertion: Either John picked up the apple, or Julius is green.