[mdcox]

Just playing devil's advocate: that doesn't necessarily rule it out. You could argue that part of your memory is lost and so it doesn't effect your identity. Or more likely, when those memories were fresh they influenced behavior which created the new more relevant memories. That would explain personality and identity progression. I also kind of like the idea that people's identity becomes less malleable as they grow older, which would make sense if it's all based on "higher order"/more specific memories.