− | <p>where the <math>a\!</math> is used in such a sense that <math>(x \,-\!\!\!< y) \prec a</math> means that from <math>(x \,-\!\!\!< y)</math> every proposition follows. With that understanding, the formula states the principle of excluded middle, that from the falsity of the denial of <math>x\!</math> follows the truth of <math>x.\!</math> (Peirce, CP 3.384).</p> | + | <p>where the <math>a\!</math> is used in such a sense that <math>(x \,-\!\!\!< y) \,-\!\!\!< a</math> means that from <math>(x \,-\!\!\!< y)</math> every proposition follows. With that understanding, the formula states the principle of excluded middle, that from the falsity of the denial of <math>x\!</math> follows the truth of <math>x.\!</math> (Peirce, CP 3.384).</p> |