context: It is unlikely that Greg is a swan. Chances are about even that Bernhard is white. Chances are about even that Mary picked up the apple.
hypothesis: Chances are about even that either Bernhard is white, or Greg is a swan.
valid_hypothesis: Chances are about even that either Bernhard is white, or Greg is a swan.
invalid_hypothesis: It is certain that either Bernhard is white, or Greg is a swan.
hypothesis_assertion: Either Bernhard is white, or Greg is a swan.