"Always start by being as vague as possible without actually waving a hoof." Cook waved a hoof. "But what really makes this work is the fact Equestria is a telegraph-and-newspaper country—and as yet hasn't come up with the idea of identity papers. Here, you are who you say you are, and national authorities aside, it's hard to prove otherwise. Since those authorities have to be pretty discombobulated at the moment, they probably can't or even won't gainsay us. Now, before we head down there, let's see if we can dunk ourselves in a stream, at least."