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Is this really true?

  1. Dec 24, 2007 #1
    Atoms that comprise your body are not atoms that you "carry around" with you throughout your life. Instead, the atoms are constantly being replaced by other atoms, and so the implications of this, is that if you go back say 10 years ago and recall a certain place where you were, the reality is that you really were NOT there, because every atom in your body has been replaced with something new?
     
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  3. Dec 24, 2007 #2

    Defennder

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    This really isn't a physics question, but I'll just put it this way, the person I am in 2007 is clearly different from me in 1997, even if every single atom of my body was preserved as it is. I in 2007 have memories of my life in 1997, but who is to say that memories can't be faked or invented? What is the "I" you are talking about anyway?

    These type of answers show how fruitless and pointless it is to engage in this type of philosophical discussions. They never seem to lead anywhere, despite the fact they have been pondered upon for thousands of years.
     
  4. Dec 25, 2007 #3

    dst

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    If there was a large shift in the atoms making up your brain, you would come to know about it.
     
  5. Dec 25, 2007 #4

    G01

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    The fact of the matter is that yes, the atoms making up your body regularly change.

    Whether this means you are a different person or not... Well, take that question to the philosophy forum.
     
  6. Dec 25, 2007 #5

    arildno

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    The overturning rate is so small that it is perfectly acceptable to say that you, as a continuous existence persists.

    Does a lake exist? A river?
     
  7. Dec 25, 2007 #6

    dst

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    Technically no, though. It's the structure and other things that matter, not the building blocks. Take a benzene atom, knock out one of the carbon atoms, and replace it with another - any difference? No. Unless every such atom is 'unique' then there is no difference whatsoever.
     
  8. Dec 25, 2007 #7

    G01

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    I never said the structure didn't matter. I was just answering his question. The atoms do change. As you say that isn't important, but, still, it was the answer to his question.
     
  9. Dec 25, 2007 #8

    dst

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    I can't believe this question is considered 'unsolved' after thousands of years. Then again, some 5,000 years after earliest dated civilisation began, I still have to wipe my own arse.
     
  10. Dec 25, 2007 #9
    On the other hand, according to quantum mechanics, the individual subatomic particles are indistinguishable, so you can't precisely say whether it is a different one or not.
     
  11. Dec 25, 2007 #10
    Your hair will still grow back if you cut it. The source of new hair molecules will come from food. Food will be grown elsewhere, and so on. If you die, the atoms in your body will disperse in the environment and will be used by something else, maybe plants, trees or bugs. It's even possible that some atoms in our bodies were used in dinosaurs 150 million years ago. Everything gets recycled.
     
  12. Dec 25, 2007 #11

    Evo

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  13. Dec 25, 2007 #12

    Kurdt

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    You could even had atoms part of you that were once part of Einstein or Rutherford or anyone else you care to think of. However you'll probably never know. :smile:
     
  14. Dec 25, 2007 #13
    True in general but there however an exception. There is alot of dinosaur bones in China, and it turned out the Chinese have been grinding them to make a dino soup. What an excellent calcium supplement.

    http://www.foxnews.com/story/0,2933,288044,00.html
     
  15. Dec 26, 2007 #14

    DaveC426913

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    Question: do the neurons in your brain replace their atoms regularly? I know neurons don't regnerate, but do they replenish their atoms?

    If not, then they literally are the same memories from 10 years ago.
     
  16. Dec 26, 2007 #15
    Yeah, I was wondering the same Dave. I think that at an atomic level, sure they must replace I'd think, because of the mitochondria doing their job.
     
  17. Dec 26, 2007 #16
    Well no crud Kurdt! LOL, thats mid-school learnings. Like the fact that the water you drink has been blood, urine, etc. etc. etc. LOL
     
    Last edited: Dec 26, 2007
  18. Dec 26, 2007 #17

    Danger

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    What?!! You don't have a machine for that?! Peasant.
    As I mentioned in another thread a few weeks back, in every breath you inhale several million, or possibly billion, atoms that comprised the body of Julius Caesar (or any other historical figure that you care to use). It's whatever retains the integrity of you that matters.
     
    Last edited: Dec 27, 2007
  19. Dec 26, 2007 #18

    Kurdt

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    I'm not a homework helper for nothing you know. :tongue:
     
  20. Dec 26, 2007 #19

    Danger

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    What??!!! You're getting paid for this?!!
     
  21. Dec 26, 2007 #20

    Kurdt

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    Due to the fact that my insights are the most valuable. :biggrin:
     
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