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Can you prove you exist?

  1. Nov 30, 2004 #1
    I've heard the phrase "I think therefore I am" as a proof of existence, but I do not find that very sound (and i think i heard that Descartes didn't exactly say that phrase).

    I believe that because we have the ability to think, either by free will or not, then we have to exist. Even if we are in a "Matrix" setting or if we are all a figment of someone else's imgination. We exist in some form, maybe just not in the reality we perceive.

    Jameson
     
  2. jcsd
  3. Dec 1, 2004 #2
    It's sound as far as it goes. Descartes used it as an axiom because for him the statement could not be false. However it is impossible to demonstrate a proof of ones existence to anybody else, and in this sense, which is the scientific or western philosophical sense, 'cogito ergo sum' is a meaningless statement, since it is untestable.
     
  4. Dec 1, 2004 #3

    Les Sleeth

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    As Canute points out, an external proof isn't possible. You are right too that in order to think a thinker must exist (anything that "does" or manifests is proof the thing exists). However, often this debate is about whether thinking itself is what defines existence, and that is definitely not true because if it were, then one would cease to exist if one stopped thinking. It is quite possible to learn to stop thinking, and when one does one becomes more aware of one's existence, not less aware. In terms of existence, all thinking makes one aware of is the existence of thinking.
     
  5. Dec 1, 2004 #4

    russ_watters

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    I exist, the rest of you are just computer simulations created for my amusement.

    Prove me wrong.
     
  6. Dec 1, 2004 #5

    arildno

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    Yes, you amuse me very much, russ..
    (I'm particularly impressed by that subprogram)
     
  7. Dec 12, 2004 #6

    "I think therefore I am" is wrong, it should be… “I believe therefore I am”....
     
  8. Dec 12, 2004 #7

    Math Is Hard

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    Microburst: If I run up to you on the street and (in a fit of rage) I bite off your little finger, how much more real is it if you think I bit off your finger vs. you believe I bit off your finger?
     
  9. Dec 13, 2004 #8

    plover

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    Hmm... needs salt...

    :bugeye: :bugeye:
    Is this something we should be worried about?
    :bugeye: :bugeye:
    How often does this impulse come over you?
    :bugeye: :bugeye:
     
  10. Dec 13, 2004 #9
    Technically, you coud be believing that you don't have your finger by having the right neurons turned off/stimulated, etc. You wouldn't see it, you wouldn't feel it, and you sure as hell couldn't see it.
     
  11. Dec 13, 2004 #10
    MIH: Believing is the “surrender” stage of the thought, where the though is now confirmed and believed to be true in your mind. If you just think and not believe you do not “actualize” ..... think about it ,..I mean believe it .... :biggrin:
     
    Last edited: Dec 13, 2004
  12. Dec 13, 2004 #11

    Math Is Hard

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    Are you saying that it is the trust level that makes the difference? If I have a thought and I completely trust it to be an experience of an event that actually happened, then I believe it?

    plover, I will not bite you. I don't like the taste of rainbirds - too dry and gamey, like duck :smile:
     
  13. Dec 13, 2004 #12

    Yes darling, you can simply think about not existing, but you will still exist, but you stop existing the day you truly believe you do not exist! & believe me you’ll never believe that! :wink:
     
  14. Dec 13, 2004 #13

    Math Is Hard

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    you're right, Micro! it would be very tough to sell myself on that!! :rofl:
     
  15. Dec 13, 2004 #14
    I find it quite simple to answer the question "How do I know I exist?"

    Pinch yourself. Do you feel pain, or any other sensation? Wouldn't this imply that because you are able to grab your own skin, because you are able to feel pain, that you exist?
     
  16. Dec 14, 2004 #15

    JPD

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    It would be particularly interesting if the finger bitten off wasn't actually there in the first place.
     
  17. Dec 14, 2004 #16
    Look, even if we were all computer programs, we still exist. You can get into a debate on our essence (are we programs? people? both? neither?), but it seems to me that whatever has an underlying essence exists. The whole "I think therefore I am" line could work if thinking implies an essence, which in turn implies existence.
     
  18. Dec 15, 2004 #17

    FZ+

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    I'm sure it is possible to prove your own existence, if you define existence that way...
     
  19. Dec 15, 2004 #18
    I really think sometimes that I'm part of someone's simulation....

    Does that mean I don't exist? Maybe, maybe not. If that above statement is true, then I exist as part of someone's simulation. If the above statement is false, then I exist "in real life"....

    But does existence in simulaton mean anything? Does existing "in real life" carry discernable meaning, and affect day to day performance in life?
     
  20. Dec 15, 2004 #19
    Really,… then you can surely read my mind, now tell me what am I thinking at this moment?
     
  21. Dec 16, 2004 #20

    JPD

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    You're thinking 'Can anyone tell me what I am thinking?'
     
  22. Dec 19, 2004 #21
    I have personally been thinking about the nature of existence a lot lately, although with a different perspective (I was looking at it with regards to the existence of God). Also, for my sins, I'm currently studying philosophy at A-Level, hoping to continue at Uni, and one of the topics covered was philosophy of mind, which hints at the nature of existence.
    Anyhow, getting to my point. Before we can decide whether we exist, we need to define existence. And therein lies the tricky part. A good example (and yes, I'm sorry, I'm going to have to refer to theology here) is the Ontological argument for the existence of God (I'm agnostic, btw). Anselm's argument is, basically, that God is that than which nothing greater can be conceived, that which exists in reality is greater than that which exists in the mind, therefore God exists. This raises 2 interesting points...it's not only existence that needs to be defined, but "reality", for surely, ideas "exist", even if they're just in the mind? Am I making sense? So existence is a nasty concept to try and pin down. An idea can "exist" in the mind, but not in reality, assuming that reality can be defined as the physical world. But then if you get into Quantum Physics, it gets tricky...Charms, Leptons etc (as far as I know) have only been proived to exist indirectly, so do they exist in "reality"? Now, where am I going with this...
    Well, basically you can use Descarte's argument, it works...but if you can argue that something "exists" in the mind, then a heck of a lot of things "exist". So it's not a matter of whether something exists, but rather where it exists (e.g. in "reality" or the "mind").

    Hope at least some of that is relevent/interesting :smile:

    Amber
     
  23. Dec 21, 2004 #22
    if I were to punch someone in the nose, would they doubt my exsistance?
     
  24. Dec 22, 2004 #23
    WolfSong: I think you’re right; the question is not if “stuff” exists rather where it exists… Does it matter if stuff exists beyond your perception? Does universe exists after you die, and will existence of universe even matter to you when you no longer perceive it. What if we are in some sort of GOD / Nature made matrix where in “reality” nothing is as it seems… :surprised
     
  25. Dec 22, 2004 #24

    As long as we both perceive punch to be a painful thing, punch is real! Or should I say relatively real… :yuck:
     
  26. Dec 22, 2004 #25

    loseyourname

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    Nope, it's only the stage at which you think you believe that you have a thought. Then we have to go back to the stage where we believe that we think that we believe that we have a thought.
     
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