Indirect proof, also known as proof by contradiction, is a method used in mathematics and logic to establish the truth of a statement. In this approach, one assumes that the statement is false and then derives a contradiction from that assumption. If a contradiction arises, it implies that the original statement must be true. This technique is often used in various fields, including geometry and number theory. For example, when proving that the square root of 2 is irrational, one assumes it can be expressed as a fraction, leading to a contradiction. This confirms the statement's validity through indirect reasoning.