Propositional Logic: Double Negation

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This video introduces the concept of the contradictory of the contradictory of a claim, or "not-(not-A)", sometimes called "double negation". It's an example of a substitution rule in propositional logic, where you can always replace "not-(not-A)" with "A".

• #education
• #propositional_logic
• #sentential_logic
• #negation
• #double_negation
• #contradictory