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If the negation of an implication is a contradiction, the implication is a tautology.
Is this correct? Because if the negation is never true, then it must be a tautology...No?
For example, I am working on a problem that, after a whole bunch of other stuff, the negation of my statement is P [itex]\wedge[/itex] [itex]\neg[/itex]P [itex]\wedge\neg[/itex]Q..which is NEVER true. And because this was the negation of an implication (IE, the only time the implication is ever false), the implication is always true...
Is this correct? Because if the negation is never true, then it must be a tautology...No?
For example, I am working on a problem that, after a whole bunch of other stuff, the negation of my statement is P [itex]\wedge[/itex] [itex]\neg[/itex]P [itex]\wedge\neg[/itex]Q..which is NEVER true. And because this was the negation of an implication (IE, the only time the implication is ever false), the implication is always true...