Why is saying that x is the same person as y, just in case y remembers being x is either false or circular.?

Please explain.Why is saying that x is the same person as y, just in case y remembers being x is either false or circular.?
You need to put more flesh in your questions. The body of your question is this: Why is saying that x is the same person as y, just in case y remembers being x...





But that is an incomplete thought. What does it mean. Yes, I understand that today I remember being ';me'; yesterday and when I was 10. But what does it have to do with false or circular......what? Logic? Reasoning? Perceptions? Identity?