context: It is almost certain that Sandra left the football. It is probably the case that Mary took the milk. We believe that Brian is a swan. We doubt that if Mary took the milk, and Brian is a swan, then Julius is green. Chances are about even that if either Sandra left the football, or Brian is a swan, then John went to the bedroom. It is highly unlikely that if Mary took the milk, and Sandra left the football, then Jeff dropped the apple.
hypothesis: It is probably the case that julius is green, and Jeff dropped the apple.
valid_hypothesis: It is impossible that julius is green, and Jeff dropped the apple.
invalid_hypothesis: It is probably the case that julius is green, and Jeff dropped the apple.
hypothesis_assertion: Julius is green, and Jeff dropped the apple.