context: It is unlikely that Daniel left the football. It is highly unlikely that John went to the kitchen. It is impossible that Julius is green. It is unlikely that if John went to the kitchen, and Julius is green, then Fred is in the kitchen. Chances are slight that if Daniel left the football, or Julius is green, then Lily is a frog. We doubt that if Daniel left the football, or Julius is green, then Mary dropped the milk.
hypothesis: It is impossible that fred is in the kitchen, and Lily is a frog.
valid_hypothesis: It is impossible that fred is in the kitchen, and Lily is a frog.
invalid_hypothesis: We believe that fred is in the kitchen, and Lily is a frog.
hypothesis_assertion: Fred is in the kitchen, and Lily is a frog.