What do you call a request with such narrowly defined parameters that the request is impossible?
What is the name for a request which has such narrowly defined parameters that the request is impossible to fulfill? More specifically, in a debate, what is the name given to the request when an opponent demands a certain proof be given, and the only proof he considers admissible is defined so specifically or narrowly that it is impossible to provide that proof. Even compelling evidence is dismissed because it is not what is specifically demanded.