context: It is almost certain that Brian is yellow. We doubt that Fred went to the kitchen. Chances are slight that Greg is a swan. It is probable that if Brian is yellow, and Greg is a swan, then Julius is a frog. It is probable that if either Fred went to the kitchen, or Greg is a swan, then Mary put down the milk. It is improbable that if Brian is yellow, and Fred went to the kitchen, then Lily is a lion.
hypothesis: It is probably not the case that greg is a swan, or Fred went to the kitchen.
valid_hypothesis: It is probably not the case that greg is a swan, or Fred went to the kitchen.
invalid_hypothesis: It is probably the case that greg is a swan, or Fred went to the kitchen.
hypothesis_assertion: Greg is a swan, or Fred went to the kitchen.