Full Idea
The proof that P→Q -||- ¬(P ∧ ¬Q) is useful for enabling us to change conditionals into negated conjunctions
Gist of Idea
We can change conditionals into negated conjunctions with P→Q -||- ¬(P ∧ ¬Q)
Source
E.J. Lemmon (Beginning Logic [1965], 2.2)
Book Reference
Lemmon,E.J.: 'Beginning Logic' [Nelson 1979], p.62