2024-10-19 11:00:03 +01:00
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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 Introduction
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This is also known as _proof by contradiction_. You start with an assumption
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declared in a sub-proof. If you can derive a contradiction from this assumption
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(typically from the introduction of another proposition and its negation), then
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you are permitted to derive the negation of the auxiliary assumption in the main
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proof.
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2024-10-20 19:50:20 +01:00
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