context: We doubt that Brian is a swan. Chances are about even that Mary went to the garden. There is a better than even chance that Lily is white. Chances are about even that if Lily is white, and Brian is a swan, then Gertrude is a mouse. It is probably the case that if Brian is a swan, and Lily is white, then John left the apple. It is highly likely that if Brian is a swan, and Lily is white, then Greg is a rhino.
hypothesis: There is almost no chance that mary went to the garden, or Brian is a swan.
valid_hypothesis: There is a better than even chance that mary went to the garden, or Brian is a swan.
invalid_hypothesis: There is almost no chance that mary went to the garden, or Brian is a swan.
hypothesis_assertion: Mary went to the garden, or Brian is a swan.