The Multiplication Stone: Two Jons is Normal?

"Who are you?" Jon asked his doppelganger. "I'm Jon. Who are *you*?" "*I'm* Jon." "You can't be, because *I'm* Jon." "No. *I* am. See, I've got *this*," Jon said, holding up the stone. His doppelganger tried to grab it. "Hey, that's mine!" "I don't know who you are, but you're *not* me. And this stone *isn't* yours." The bedroom door opened and Karyn walked in. "Hey! What are you two doing in my room?" "Wait a minute," Jon said. "You're not confused that there are two of me?" "Why would I?" Karyn asked. Karyn didn't hear Jon's wish, so when the stone created Jon's doppelganger, reality (including Karyn's memories) changed so that it was normal. But what could possibly be the reason that there were two Jons?