Reductio ad absurdum is a logical argument proving a statement false by showing it leads to a contradiction or an…
Negation elimination is a fundamental rule in natural deduction. It permits inferring a conclusion by negating a premise, provided it…
An indirect proof, also known as proof by contradiction, involves assuming the opposite of what you want to prove. If…
The law of excluded middle states that for any proposition, it is either true or its negation is true. There…
Double negation is the logical principle where applying negation twice to a statement returns the original statement. In classical logic,…
Consequentia mirabilis, a classical logic principle, asserts that if the negation of a statement leads to a contradiction, the original…