context: It is almost certain that Jeff went to the hallway. Chances are slight that Lily is white. It is unlikely that Greg is a swan.
hypothesis: There is a very good chance that either Greg is a swan, or Lily is white.
valid_hypothesis: It is probably not the case that either Greg is a swan, or Lily is white.
invalid_hypothesis: There is a very good chance that either Greg is a swan, or Lily is white.
hypothesis_assertion: Either Greg is a swan, or Lily is white.