context: It is likely that Fred went to the garden. Chances are about even that Gertrude is a cat. It is likely that Bernhard is a swan. It is highly likely that if Bernhard is a swan, or Fred went to the garden, then Antoine is thirsty. It is highly likely that if either Bernhard is a swan, or Gertrude is a cat, then Mary moved to the office. It is impossible that if Fred went to the garden, or Gertrude is a cat, then Greg is a frog.
hypothesis: We doubt that either Fred went to the garden, or Greg is a frog.
valid_hypothesis: It is probably the case that either Fred went to the garden, or Greg is a frog.
invalid_hypothesis: We doubt that either Fred went to the garden, or Greg is a frog.
hypothesis_assertion: Either Fred went to the garden, or Greg is a frog.