07.2 Proof by Contradiction
7.2 Proof by Contradiction Proof by contradiction proves a statement by showing that its negation is impossible. Instead of proving $P$ directly, we assume $\neg P$ and derive a contradiction. The logical form is: $$ \neg P \Rightarrow \bot. $$ Here $\bot$ denotes contradiction. Once contradiction is reached, classical logic allows us to conclude $P$. This method is useful when the desired conclusion is difficult to construct directly, but the...