In terms of the body replacing itself, I think the 'me' part would be the mind. Unlike other cells in the body, brain cells are not regenerated. New connections are made as new memories and thoughts appear, but the cells themselves largely remain the same. As for "why am I me?", I would have to say that genetics and environmental factors shape the personality early in life, and continuing experience continues to shape it into early adulthood (not to say older adults can't change, but it is less likely that they will be open to significant change).
John Adams Wrote:The Government of the United States of America is not, in any sense, founded on the Christian religion.