context: There is little chance that Greg is a swan. Chances are about even that John picked up the milk. There is a very good chance that Lily is white. There is a better than even chance that if John picked up the milk, or Greg is a swan, then Sandra got the football. It is probably not the case that if either Greg is a swan, or John picked up the milk, then Julius is a frog. There is a very good chance that if Greg is a swan, or John picked up the milk, then Mary is in the park.
hypothesis: There is a very good chance that mary is in the park, and Greg is a swan.
valid_hypothesis: It is improbable that mary is in the park, and Greg is a swan.
invalid_hypothesis: There is a very good chance that mary is in the park, and Greg is a swan.
hypothesis_assertion: Mary is in the park, and Greg is a swan.