Ah, the classic Ship of Theseus. I always find students treat it as a neat tidy puzzle, but it really opens a Pandora's box. If you strip every plank, replace it, do you still have the same ship? Or is it an identical replica? When applied to a character, the answer depends on whether identity is a bundle of traits or an underlying continuity. If a person forgets their childhood, learns a new language, adopts a new moral stance—are they still "the same" person? I tend to lean toward continuity of psychological connection: memory, narrative, sense of self. So yes, they are the same person, even if their surface has changed, unless you decide that identity is solely the sum of the parts, in which case they become a new individual. In short, it’s not a clean switch but a gradual shift in what defines “self.”