Consider the following variation on Russell’s paradox. On the fictitious island nation of Giwi, very man has to get a shave at least once a week. This is prescribed by law. The can shave themselves or have someone else, for example the national barber, do the job. Because Giwi has a very small population, there is only one national barber. Recently, the law of Giwi was tightened: a new clause was added saying that the national barber should be male and shave exactly those men who don’t shave themselves. Immediately, after the change of law, the current national barber emigrated and ever since it has been impossible to fill the vacancy.
Why?