Negative elimination

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Changed: 1c1,11

Negative elimination is basically the rule of double negatives: "it's not the case that it's not raining" means that it's raining. Likewise, it's logically consistent to claim that "it's raining" means that "it's not not raining".

Negative elimination is basically the rule of double negatives: "it's not the case that it's not raining" means that it's raining. Likewise, it's logically consistent to claim that "it's raining" means that "it's not not raining".

Formally:

¬ ¬ A
∴ A

also

¬ ¬ ¬ A
∴ ¬ A

Negative elimination is basically the rule of double negatives: "it's not the case that it's not raining" means that it's raining. Likewise, it's logically consistent to claim that "it's raining" means that "it's not not raining".

Formally:

  ¬ ¬ A
  ∴ A

also

  ¬ ¬ ¬ A
  ∴ ¬ A