Am I the same person today that I was when I was 2 years old?

I imagine that you've put on a few pounds since then, but you gave the game away with the word "I". You can only use that word to refer to one person, namely yourself. So if there is any person you can describe as "the person I was when I was two", it's the same person as the one you can describe as "the person I am today".

If you want to leave open the question whether a single person has persisted over time occupying the body that you now inhabit, ask it...well, that way. I'm guessing the answer to that one is also yes, unless you're the sort that sends yourselves birthday cards.

See also the discussion in response to this question.

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