Paradox of the barber

The Paradox of the Barber is a logical puzzle that examines self-reference and sets. It describes a barber who shaves everyone who does not shave themselves. The paradox arises when we ask, "Who shaves the barber?" If he shaves himself, according to the rule, he shouldn't shave himself. If he doesn't shave himself, then he must shave himself. This creates a contradiction, illustrating the complexities and limitations of self-reference in logic and set theory, similar to other well-known paradoxes like Russell's Paradox. It challenges our understanding of definitions and classifications within mathematics and philosophy.