If we accept that the many-worlds interpretation of quantum mechanics is true in a sense that it is experienced by everyone in reality, we can present the argument that you are not affected at all when you disappear with a certain probability. Even though this interpretation may be an assumption, it should be considered since it pertains to an event that occurs to everyone. In particular, we can consider a problem in which a certain upper limit exists; the result will be completely unknown below this limit. In principle, our argument can explain why the result will be completely unknown below the upper limit. By considering the transition of copies over time, we can consider a principle and let it be the basis of our argument. We classify propositions by presenting a formalized version of... our argument. Using the concept of the length of description, we achieve this objective by considering the rule that determines which copy is chosen from many copies of you. We eventually employ the hierarchy of axiom systems of different strengths known in mathematical logic as the length of description.