context: It is probably not the case that John took the apple. There is a very good chance that Julius is a rhino. It is unlikely that Greg is a swan. There is little chance that if John took the apple, or Julius is a rhino, then Bernhard is a frog. It is probably not the case that if either Julius is a rhino, or John took the apple, then Lily is a frog. There is a better than even chance that if Julius is a rhino, or Greg is a swan, then Mary got the milk.
hypothesis: It is probable that either Lily is a frog, or Julius is a rhino.
valid_hypothesis: It is probable that either Lily is a frog, or Julius is a rhino.
invalid_hypothesis: Chances are slight that either Lily is a frog, or Julius is a rhino.
hypothesis_assertion: Either Lily is a frog, or Julius is a rhino.