17 lines
528 B
Markdown
17 lines
528 B
Markdown
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---
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tags:
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- logic
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- propositional-logic
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---
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# Negation Elimination
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Like the [introduction](Negation_Introduction.md) rule for
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negation, the elimination rule also works by deriving a contradiction. It is
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basically _Negation Introduction_ in reverse. Instead of starting the sub-proof
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with a true proposition from which you derive a contradiction, you start with
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the negation of a proposition, derive a contradiction and then assert the
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positive of the negated proposition you started out with.
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