Really, it's gotta be there. Twins have to wonder strange things about their very state of being: Am I the original or the copy? Does my twin know what I'm thinking? Is _____ really my name, or was it my twin's name before we got mixed up by our parents?

I figure that last question applies to all sets of identical twins. The question isn't "Have our parents ever unwittingly mixed us up," it's "were we mixed up an even or an odd number of times?"

Maybe I'm overthinking this.