2022-04-23 13:26:53 +01:00
										 
									 
								 
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											2024-06-16 18:30:03 +01:00
										 
									 
								 
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								tags:
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								  - logic
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								  - propositional-logic
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											2022-12-25 16:00:05 +00:00
										 
									 
								 
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								# Negation Introduction
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											2024-02-02 15:58:13 +00:00
										 
									 
								 
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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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											2022-12-25 16:00:05 +00:00
										 
									 
								 
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											2024-02-16 16:14:01 +00:00
										 
									 
								 
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