Peirce's Law - Other Proofs of Peirce's Law

Other Proofs of Peirce's Law

Showing Peirce's Law applies does not mean that P→Q or Q is true, we have that P is true but only (P→Q)→P, not P→(P→Q) (see affirming the consequent).

simple proof: (p \rightarrow q) \rightarrow p \Rightarrow \overline{p \rightarrow q} \or p \Rightarrow \overline{\overline p \or q} \or p \Rightarrow (p \and \overline q) \or p \Rightarrow (p \and \overline q) \or (p \and 1) \Rightarrow p \and (\overline q \or 1) \Rightarrow p \and 1 \Rightarrow p.

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