At present, to our knowledge there are five us us: we use the identifiers G, N (that's me), M, F, and B. This is primarily because some of us at this time don't have full names, and because identifiers (chosen as an initial or for a different reason) can be faster to think and/or type.
Think of this as a shared journal, except that the sharers use the same brain. Are we insane, or just delusional? Not a clue, and I've come to the conclusion that it doesn't really matter. I am what I am; as long as what seems to be acts exactly as it should (if the duck quacks like a duck and doesn't suddenly sprout paws, say), there's subjectively no difference between whether it is or isn't[ what it seems to be].
If the above paragraph seems a little confused, my apologies; it was written past midnight, when preparing to go to sleep. If you want to know anything else, ask me. (There may still be some work to be done on this description.)