context: Chances are slight that Sandra dropped the milk. Chances are about even that John got the apple. There is a very good chance that Yann is tired. It is impossible that if John got the apple, and Sandra dropped the milk, then Mary left the milk. It is probable that if Yann is tired, and John got the apple, then Greg is a swan. It is probable that if Sandra dropped the milk, or Yann is tired, then Julius is a rhino.
hypothesis: There is almost no chance that either Mary left the milk, or John got the apple.
valid_hypothesis: Chances are about even that either Mary left the milk, or John got the apple.
invalid_hypothesis: There is almost no chance that either Mary left the milk, or John got the apple.
hypothesis_assertion: Either Mary left the milk, or John got the apple.