Laws of Thought

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  Laws of Thought
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    Identity

    Whatever is, is

      Every A is A.

        EXISTS A

          A=A

            A <-> A

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    Contradiction

    Nothing can both be and not be

      Nothing can be A and not A

      Everything cannot both be and not be

      Everything cannot be A and not A

         A IFF A

            A XOR !A

              A >< !A

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    Excluded Middle

    Everything must either be or not be

        Everything is either A or not A.

        Nothing can be neither A nor not A

            A OR (NOT A)

               A | !A