Question 1195749
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/ ∴ P ⊃ P

               |1. ~(P ⊃ P)         Assumption for indirect proof
               |2. ~(~P v P)         1, Material implication     
               |3. ~~P • ~P          2, DeMorgan's law
               |4. P • ~P            3, Double negation
5. P ⊃ P           lines 1-4     Indirect proof

Edwin</pre>