User:Lord Farin/Tableau Proof Rules/Not-Elimination

Principle of Non-Contradiction
Given $p, \neg q$, we have contradiction ($\bot$).


 * align="right" | $k$ ||
 * align="right" | $I,J$
 * $\bot$
 * Principle of Non-Contradiction: $\neg \mathcal E$
 * $i,j$
 * $i,j$