context: Chances are about even that Brian is a swan. It is probably the case that John is in the office. There is little chance that Fred dropped the apple.
hypothesis: It is probably not the case that brian is a swan, and John is in the office.
valid_hypothesis: It is probably not the case that brian is a swan, and John is in the office.
invalid_hypothesis: It is probable that brian is a swan, and John is in the office.
hypothesis_assertion: Brian is a swan, and John is in the office.