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I think, therefore I am

  1. Jun 28, 2004 #1
    Cogito Ergo Sum. I think, therefore I am. - Rene Descartes

    Can this be used as proof of one's existence?
    Can you prove that you exist?
  2. jcsd
  3. Jun 28, 2004 #2
    Sadly, no one can improve on or expand on the profoundness of this statement.

    It also gets the fatalistic camp upset cause there ain't no way to refute.

    nuff said, love & peace,
    olde drunk
  4. Jun 29, 2004 #3
    it's a bit like saying "I move so therefore I exist"

    If one thinks of thinking as movement.

    If you cease to move you are dead..... yes?
  5. Jun 29, 2004 #4


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    It's like an otological argument.

    Although "cognito ergo sum" is famous, it's not a 'persuasive' proof of existance, much like the ontological arguments (which Descartes also tried his hand at.)

    Consider, for example, that I can imagine a flying pink unicorn that thinks, and, since it has existential quanderies, posits "rosa ergo sum sum" - "I am pink therefore I am". Does this flying pink unicorn exist?

    Existential arguments of the form "I __ therefore I am" are all circular, and of the form "I therefore I."
  6. Jun 29, 2004 #5


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    No. It's about doubting. Descartes could doubt that his arm or leg or any part of his body "really existed" - they could all be illusions after all. But he couldn't doubt the existence of the thing (whatever it was) he did the doubting with. So that was in a differennt category from the body. Category 1: things I can doubt. Category 2: things I can't doubt. Hence "cartesian dualism".
  7. Jun 29, 2004 #6
    I, the Ego. Regardless of what I might think, the process itself supports that I, the Ego, cannot doubt myself.
  8. Jun 29, 2004 #7
    As I've said before in other similar threads; "I am; therefore, I think."
    The mere fact that I or anyone can say or think "I am." proves their existance to them. Being aware that one is conscious and conscious of ones self is all that is required. Thinking is a result or attribute of being and being conscious.
  9. Jun 29, 2004 #8


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    This thread needs a link to Descartes Meditations. . If you want to have a meaningful discussion of "Cognito, ergo sum". You should read all 6 of the Meditations.
  10. Jul 3, 2004 #9
    Hey, Royce. Long time, no see :smile:.

    You're absolutely right here. A common misunderstanding of "I think therefore I am" is that it is reversible ("I am therefore I think"), which would lead to the consequence that non-thinking things do not exist, which is clearly flawed. But, as you aptly pointed out, thinking is a result of being and being conscious, which is why being able to think about not existing proves that there is some existing "thinker".

    Descartes had created an illustration of sorts, wherein a powerful demon tried to convince Descartes that everything he believed to be true, was in fact false. The demon could indeed decieve Descartes, up to the point of trying to convince him (Descartes) that he (Descartes) didn't exist. After all, if Descartes can think about the possibility that he (or anything else, really) doesn't exist, then that means that Descartes can think. And, if Descartes can think, then he must exist. If he didn't, who would be doing the thinking?
  11. Jul 5, 2004 #10
    I'm not sure what kind of "proof" you want, but it is a philosophical statement concerning the cognitive sciences. According to them, there is no way to use it to prove anything and, in fact, it may be quite misleading. In addition, "existence" itself is a hotly debated issue in philosophy and has no clear identity (see, Stanford online). Hence, both scientifically and philosophically the meaning and validity of the statement are of dubious value. However, that is not say it has no emotional value.... :smile:
  12. Jul 7, 2004 #11
    behind door number one

    “I am thinking therefore I exist” is probably a better translation of what Descartes said, (http://www.open.ac.uk/Arts/bshp/beaney/teaching/emp/descarte/cogito.htm [Broken]). There are two primary cruxes in this statement that need to be addressed, the concept of “I” and in turn what does it mean to “exist”.

    First let’s to try to get a grip on this “I”, “me”, “self” thang.
    Hume did a pretty good job on summing up the “I” when he took ‘Cogito Ergo Sum’ to the extreme and boxed it up in solipsism; basically the idea that all you can ever really know is your own thoughts which can be considered the “I”; thoughts = something semantically referred to as “I”.

    Number two, Exist or in other words ‘to have actual being or be real’ is another story and frankly requires a leap of faith or more practically know these days as a kind of ‘leap of phenomenology’, (http://plato.stanford.edu/entries/phenomenology/#1). ‘To exist’ is equal to ‘something real’ which is how I define myself based on the world around me which is something that can NOT be proven to exist because it is after all only thought; I know, a bit circular to say the least, (thanks NateTG).

    So, have faith in anything, the physical laws of the universe as you and I know them, faith in rain, in the blue collar, the right wing, the Buddha, pencils, flying pigs etcetera. In other words it’s a kind of create your own existence gig.

    So to answer the question, neither Descartes discourses nor the simple statement in the sentence I am writing at this moment prove that you exist when defined as above.

    Discourse I: :rolleyes:
    When there is enough universal energy vibrating with a particular force it creates a critical mass where/when consciousness takes form. Why the particular energy mass you and I experience fragmented into a bunch of “I(s)” is most likely something ‘I or you/you or I’ will never know until ‘our or the’ energy state changes. After all, wasn’t it a fairly respected shared energy fragment that once said “an organism can never be defined by itself but only by a higher organism”. Or to rephrase in slightly more hippy terms “an energy consciousness can never be defined by itself but only by a different energy consciousness”. ??

    That said, I actually take back my remark about Descartes statement. If we are just simply energy waves, (or particles, or strings, or whatever else you would like to call it/us) that have bought into the same vibration of reality then Descartes was kind of correct. But you really can’t get the whole picture from his translations. Probably the better way of wording it would be “I am thinking therefore I can exist” :eek:
    Last edited by a moderator: May 1, 2017
  13. Jul 7, 2004 #12
    Hey, Mentat, Yeah, Its been a while. Good to "see" you too! :smile:

    Descartes was writing in the first person. In his first meditation of the six he stated that he could bring into doubt everything that he had presumed to know except the one truth; "I am."

    "I am." is a simple statement that has truth only for "I" of that statement; however, that truth is absolute and undeniably for "I" because for something to state "I am." there has to be that something, some "I".

    The statement does not make any claims as to what or who "I" is, only that it is. Nor, does the statement make any presumtions about what "am" is or in what form "am" is. "am" simply states a state of being whatever that may be.

    "I am." is the only absolute, undeniable truth that I can establish and prove to myself incontrovertably. I cannot prove it to you or anyone else just as I cannot prove that you or anyone else exists.

    I can, however, prove to myself that there is that that exists, "is", outside of myself, "I." I cannot prove that that which is outside of myself is another being or a machine. I can only prove that there is also something other than "I" that is.

    "I" may be a wave, a particle, a probablity function, a person, a god, a universe or the entire cosmos. It doesn't matter nor does the statement make any such distinctions. It states simply and truthfully that "I am."

    Perhaps it would be clearer if it stated; "I think; "I am"; therefore, I am."
    Last edited: Jul 7, 2004
  14. Jul 8, 2004 #13
    Yo Royce,
    I’m kind of new to this whole PF thing and I hate to butt in; however, “my” conscious wouldn’t let me sleep at night unless "I" pointed out an inconsistency in your statement they may simply need a bit of clarification. Or this could simply be a flaw in my “I”ness.

    ("I am." is the only absolute, undeniable truth that I can establish and prove to myself incontrovertably. I cannot prove it to you or anyone else just as I cannot prove that you or anyone else exists.

    I can, however, prove to myself that there is that that exists, "is", outside of myself, "I." I cannot prove that that which is outside of myself is another being or a machine. I can only prove that there is also something other than "I" that is.)

    Are you to say that “I am” is an absolute and “is” a theory? How would one go about proving this particular idea in the context of this discussion? To clarify, how do you interpret Descartes MM to reflect that he or anyone, (if they do exist outside of the “I”) is able to prove that anything exists outside of the “I am”? Or maybe you are pointing to the fact that their may well be different states of proof(s)?
    You know like “incontrovertibly” and “controvertibly”?
    Thanks in advance for the clarification..
    Also, I do apologize if this reply is considered in bad PF etiquette.
    Last edited: Jul 8, 2004
  15. Jul 8, 2004 #14
    Proof to who? Outside of the thinkers own thoughts, there is no existence.

    I think this statement does the opposite of prove physical existence, it gives rise to the thought that only thought exists.
  16. Jul 8, 2004 #15
    I'm not so sure on this point, Jubal. What is the difference between saying that there is an "I" and saying that there exists an "I"?
  17. Jul 8, 2004 #16
    Forgive me for answering when you addressed it to Royce but...

    You appear to be treating "I am" as an entity, rather than a statement about an entity. "I am" means "there is such a thing as me". Descartes' statement (I think therefore I am) shows irrefutable proof (though only irrefutable if directed at oneself...i.e. it proves it to you, but not necessarily to anyone else) that the person making the statement exists.

    To be clear, if one were to always speak the statement audibly, then it could be changed to "I speak therefore I am" and still be making the same point, since if there were no "I" then who would be doing the speaking?
  18. Jul 8, 2004 #17
    That’s cool,
    What I was trying to say is that - to say that there “exists an “I” is relative to ones identity, (defining who “I am”) which is a construct of ones environment, (thing or things that exist outside of ones being or the concept of “I”).

    In the context of this discussion I would say that “exist” infers a relation to the environment outside of the “I”. In essence that there is/are constructs of any sort that exist outside of ones one’s thoughts, (the inverse to be true).

    But then again, it’s 1 AM and I just got home from a pub so I am not 100% sure that the above is a coherent statement.??? not an excuse just a bit of “I”.. ;)
  19. Jul 9, 2004 #18
    Response to post #16

    No worries, I was simply asking for clarification from Royce regarding his statement and how he was defining “I am”.

    Regarding your statement:

    Descartes' statement (I think therefore I am) shows irrefutable proof (though only irrefutable if directed at oneself...i.e. it proves it to you, but not necessarily to anyone else) that the person making the statement exists.

    I guess that it depends on how you define/interpret from Descartes meditations the construct of “exist(s)”, (see post 17, a response to post 15) “I am” and “exist” are not interchangeable even by Descartes standards.
    Anyway, I’m pretty sure we are saying the same thing which is that all anyone can prove is that “I” experience thought. “Thought” is what defines “I” which is all that can be known to any degree of certainty which in turn precludes the idea that anything exits outside of that.

    PS don’t you think Descartes was a little pronoun centric.. ;)
  20. Jul 9, 2004 #19
    Jubal, in response to your questions, posts and Mentat's comment, I approached Descartes statement; "I think; therefore, I am" more semantical than philosophically. "I" of course refers to the writer or speaker. "am" is a form of the verb "to be" which is the same a exist; I,the writer, am, exist. The statement is axiomatic or self evident. As Mentat said for someone or thing to say, write, think; "I am" there must be, exist an "I". It is necessary first for there to be an "I" prior to there being a statement or thought of the state of I's existence or nonexistence. "I am." is a complete statement and a fore gone conclusion or better necessity. This is, however as we agree true only for the speaker, writer, thinker, "I".

    As to my statement that I can also prove to myself that there is, exists something, someone outside of myself, I have written this proof here at the PF's before and didn't think it necessary to repeat it. "I am." is an axiom of absolute undeniable truth. That something exists outside of me is at best a provable and verifiable theory. Simply, all that it takes is for me to be given any one bit of information or knowledge that I do not already know and could never have known and be able to verify that knowledge is true. I gain knowledge not only that there exist something outside of me but something about that which is outside of me. Once that is proven then everything else can, if I am clever and logical enough deduce that there are others and other things outside of myself and that there is therefore some truth, validity to what my senses are telling me. From here I can with some degree of assuredness know the universe, reality and other being too exist. This is the only way that I have found to get beyond the one absolute truth; "I am."
    Another way of putting it is If I can learn anything that I did not previously know, I, then, have proof the there exist that which is other than me.
  21. Jul 19, 2004 #20
    The Christ Consciousness

    According to my experience, the " I " that states " I " (the awarness) that someone, or something is stating this, and observing beyond my conscious self is what some call The Christ Consciousness, (sub-conscious) This is where all thoughts flow, before we are even aware they exist. The sub-conscious is working on a soul level, existing outside the physical plane. All souls are derived from or born by The Great Soul, Energy, Master of the Universe, God, whatever. Just the fact that you are aware this exists means that you can tap into this Universal Consciousness and gain more awareness of who you are, on this plane, and why you are here?? Obviously everyone who has been responding on this issue, can identify with the " I " we are talking about. If all who are discussing this, are aware of its presence, there must be some connection. Being able to tap into this perception is a gift, you can monitor your actions. When your body, mind, and spirit (gateway to the Universal Soul) are able to consistently align these two (sub-conscious and conscious) together in perfect unison then you have reached your destination. You will just be. or at least you sure as hell won't be here!
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