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Disjunctive Laws


  1. Disjunction is commutative: for all formulas A and B
    A \/ B iff B \/ A.
  2. Disjunction is associative: for all formulas A, B, and C, we have
    A \/ (B \/ C) iff (A \/ B) \/ C.

Proof: by truth tables.

Author: Wolfgang Schreiner
Last Modification: October 6, 1999

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