What's that Language?

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Across
  1. 3. modustollens
  2. 6. contrapositive
  3. 8. simplification
  4. 10. Biconditional
  5. 11. implications
  6. 12. conjunction
Down
  1. 1. Identitylaws
  2. 2. Contradiction
  3. 4. Distributivelaws
  4. 5. inverse
  5. 7. Commutativelaws
  6. 9. Idempotentlaws