context: It is probably not the case that Julius is yellow. Chances are slight that Greg is a swan. It is improbable that Mary left the football.
hypothesis: It is probably the case that mary left the football, and Greg is a swan.
valid_hypothesis: There is almost no chance that mary left the football, and Greg is a swan.
invalid_hypothesis: It is probably the case that mary left the football, and Greg is a swan.
hypothesis_assertion: Mary left the football, and Greg is a swan.