The liar paradox arises when a statement refers to itself in a way that creates a contradiction. A classic example is the statement "This statement is false." If the statement is true, then it must be false, but if it is false, then it must be true. This self-referential nature leads to a logical inconsistency. Philosophers and logicians, such as Epimenides and Bertrand Russell, have explored the implications of the liar paradox. It challenges our understanding of truth and language, prompting discussions about the foundations of logic and the nature of self-reference in statements.