context: We doubt that John discarded the milk. It is highly likely that Fred went to the kitchen. It is probably not the case that Greg is yellow. Chances are slight that if either John discarded the milk, or Greg is yellow, then Brian is gray. It is unlikely that if Greg is yellow, and John discarded the milk, then Yann is tired. There is almost no chance that if John discarded the milk, or Fred went to the kitchen, then Sandra left the milk.
hypothesis: We believe that yann is tired, and Fred went to the kitchen.
valid_hypothesis: It is impossible that yann is tired, and Fred went to the kitchen.
invalid_hypothesis: We believe that yann is tired, and Fred went to the kitchen.
hypothesis_assertion: Yann is tired, and Fred went to the kitchen.