context: It is highly unlikely that John took the football. We doubt that Lily is a swan. There is a better than even chance that Sandra got the apple. We believe that if either Lily is a swan, or John took the football, then Gertrude is a cat. It is impossible that if either Sandra got the apple, or Lily is a swan, then Brian is white. It is probably not the case that if John took the football, and Lily is a swan, then Julius is gray.
hypothesis: It is impossible that brian is white, and Sandra got the apple.
valid_hypothesis: It is impossible that brian is white, and Sandra got the apple.
invalid_hypothesis: It is probably the case that brian is white, and Sandra got the apple.
hypothesis_assertion: Brian is white, and Sandra got the apple.