context: It is certain that Brian is white. It is highly unlikely that Greg is a swan. It is likely that Lily is white.
hypothesis: Chances are about even that either Greg is a swan, or Brian is white.
valid_hypothesis: It is almost certain that either Greg is a swan, or Brian is white.
invalid_hypothesis: Chances are about even that either Greg is a swan, or Brian is white.
hypothesis_assertion: Either Greg is a swan, or Brian is white.