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Cogito ergo sum, however, I dont know you exist, prove to me you exist

  1. Feb 4, 2010 #1
    "I think therefore I am".... This means that I know I exist but I dont know you exist... This then leads onto metaphysical skepticism. The whole universe and everyone and thing in it, except for myself does not exist, other than within my own thoughts.

    Keeping this simple. If we consider the big bang, the creation of the universe seems to be impossible as to why it happened in the first place. Not how, but why. It would be far simpler to conclude it didnt happen and therefore does not exist. This supports: I think therefore I am but you may not exist.

    "Cogito ergo sum,.. however, I dont know you exist, prove to me you exist."
  2. jcsd
  3. Feb 4, 2010 #2


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    That doesn't follow.
  4. Feb 4, 2010 #3
    think ...
  5. Feb 4, 2010 #4
    Prove to me you think.
  6. Feb 6, 2010 #5

    Doug Huffman

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    Not 'metaphysical skepticism'.

  7. Feb 6, 2010 #6
    Well, this is silly. I take this to mean that my brain is capable of producing every physical experience I have, and within a set of boundaries that make up all the laws my mind has written, including ones I haven't consciously become aware of yet. I suppose then as well, since a human brain isn't capable of this feat, that my being must be self-deceived, that some other "organ" is producing my experience.

    This is one helluva holodeck!
  8. Feb 6, 2010 #7
    That would be incorrect. Brain is a physical thing. Solipsism doesn't require physical things, its about the 'self'. The idea being that what we consider 'brain activity' is just a small part of the self.
  9. Feb 10, 2010 #8
    Which is why I referred to "some other organ" producing my experience, whatever that may be.
  10. Feb 10, 2010 #9
    But that would still be missing the point, as self doesn't imply the need for any organs. The point is that you don't really need to know what self is, where it comes from, or what if anything causes it. That is not important part.
  11. Feb 10, 2010 #10
    Err, sorry. I wasn't trying to limit "organ" to anything physical.

    Something is an agent (if that word is acceptable in place of organ) that is responsible for my experiences. I'm saying that this agent would be unreasonably powerful, nearly if not wholly god-like, to produce such a consistently stable universe I experience. And that's just silly. Because with that scope of talent or ability, I shouldn't be so limited in my present experience, unless I sandboxed myself in a limited consciousness/awareness. Possible, but silly.
  12. Feb 10, 2010 #11
    Yes, it is a silly theory of existense, but Descartes is not advocating it as such.
    Descartes was making an argument against radical skepticism.

    The important part is, while it may seem silly to believe otherwise, we can't say for 'certain' that the external world exists. And Descartes was looking for something 'certain', on which he could base his philosophy.

    Descartes was a rationalist, so he believed that all knowledge could be logically deduced. All he needed was a first principle, which he could know with absolute certainty.

    We might think solipsism is silly, and most people would actually have a very difficult time maintaining it as a philosophy, but we can't be 'certain' that the outside world exists.

    So what can be be certain about?
    For Descartes, there can be certainty that the 'thinking self' exists.
    So, this becomes his starting point. From there he uses logic to deduce other things.

    Descartes was not advocating solipsism.
  13. Feb 15, 2010 #12
    I am.

    I'd not call the state of "amness" (self-awareness) just a thinking state.

    Thinking is usally very connected to usage of human language.

    I can chose to silence my brain to the point it produces no thought, not even a single word, yet, I am AWARE of my presence/existence.

    Thus, to me, it's way more logical to state with certainty this:

    1. I am, therefore I exist.

    And from this statement I'd deduce these two, which to me are also certainty:

    2. Since I exist existence must be eternal, or I could never exist.

    3. Given eternity supreme being(s) had to evolve.

    Now, we can discuss what existence is (no matter what it is, it still IS), what supreme beings might be and to what level they evolved, etc. Well, to me it's a certain thing that there must be a being who evolved way above our human current state of evolution (especially in capacity of understanding and way of being). I imagine supreme beings as beings of a very high (if not highest) state of awareness, and deep (if not deepest) state of love.

    Some might call such a being God, but to me, it's more a state of beingness than being itself.

    And sure, we can discuss if you exist for real, or just in my mind...

    To me, it doesn't really matter how I and/or you exist, the important thing is experience of existence -- if all of it is just in my mind, or physically true, or whatever, it's not of any real importance, the only important thing is recognizing existence, experiencing and feeling it, learning from it and evolving (I'd call this progressing in our individual eternal soul's consciousness).

    I see life like a process, a process of going from lowest state of awareness to the highest possible one. (Via our soul, which is not bond to one life-time or one life-form.)

    Awareness is all there is. It includes me, you and everything. There is no you, nor me, because we are all the same stuff. Thus, there is only one "I".

    I am.

    Awareness is.

    Last edited: Feb 15, 2010
  14. Feb 15, 2010 #13
    Of course not, but that doesn't really tell you anything.

    For instance:

    I am, therefore I exist
    I am, therefore I am
    I exist, therefore I am
    I exist, therefore I exist

    In each case, you have a tautology. Something that is true by definition, but not something that follows from something else. You're just using different words.

    But, lets take a step back.
    What is the question?

    Can I, honestly, doubt that I exist?
    Can I be certain that I exist?

    Descartes was not concerned with 'whether or not' he existed, but rather if it was possible to "know for certain" that he did.

    So, your tautology is not helpful.

    One can, however, contemplate a thing that 'exists' but does not think. A rock, for instance. So thinking and existing are not the same.

    Now, I can doubt that you exist, you might be a clever AI, or a dream, and I can doubt my computer exists because sense data is often contradictory.
    That said, I'd have be a pretty hardcore skeptic to consider this doubt I have to be valuable. But I can always honestly doubt the outside world.

    Can I doubt that I exist?

    "X" therefore I know I exist.

    In order for me to be certain I exist, X has to be self-evident, undeniable, and it has to imply that I exist. I can't just repeat myself, or that is a circular argument.

    I doubt many things, therefore I am a thing which doubts.
    If I am a thing which doubts, then that thing which doubts, must exist.

    "I think therefore I am" is not a tautology. The 'I think' part is self evident, and the 'I am' part follows from this.
  15. Feb 15, 2010 #14
    I see it just the opposite.

    I am therefore I can think, or not.

    Being is a given (at least while we are alive), while thinking is a matter of choice, but usually it's more useful to think than not, but not always, when one wants to really concentrate/focus/meditate thoughts are not welcome.

    The state of Amness is what enables us to be aware, to think, to feel.

    Obviously a rock isn't in the same state of amness as we are, but it surely is in its own state.

    And the way I see it, there are countless of states of amness/awareness.

    From total non-awareness (which would be perfect void) to total awareness (which would be "final", or highest awareness), and all in between. And that in between is an atom, a rock, a plant, an animal, a human, and who knows who and/or what more.

    To conclude, first is amness, only then can arise though and thinking (and for a thinking being it has to be at certain "height").

    You didn't comment on my 2nd and 3rd premises, which I'd like you to invite to do so. I value your insights even if I don't (yet) agree with all you share.
  16. Feb 15, 2010 #15


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    Being is not a given. The only thing we know for certain is that we are thinking. We do not know for certain what is doing the thinking. But we can label this thing as "I", whether it is even corporeal or part of a computer simulation.
  17. Feb 15, 2010 #16
    First is existence, only then can arise thought and thinking.... fine.
    This is an ontological statement, a statement about being.
    Yes, thinking implies existence, but Descartes wasn't making an ontological argument.

    He was making an epistemological argument.
    An argument about what can be known (for certain).

    The question is not 'whether I exist', but 'whether I can know that I exist'.
    Until we are talking about the same thing, I don't think you would get any value out of it.
    There are many people who come to this forum who say the exact same thing as you have just said. Its not 'wrong', per se.... but it is not what Cogito Ergo Sum is about.
  18. Feb 16, 2010 #17
    I used word "being" in sense of "existing", but being to me means something more than just existing, it also means being aware of existing. For example, a rock is existing but is probably not aware of own beingness, while a human being is existing but also aware of own existence and beingness.

    I agree though, that we cannot know for certain who is doing the thinking, but whoever or whatever that is, it is existing and also is in state of beingness (it IS!), since it's not only existing but also being aware of it.

    And the main part of my statement was, that thinking cannot exist without something first existing/being.
  19. Feb 16, 2010 #18
    If I know for certain that I am thinking, then I also know for certain that I am being/existing, or else I couldn't be thinking. Agree?

    I'd like to explain a bit better though why I disagree with statement "Cogito Ergo Sum":
    I cannot know for certain that I am thinking, first, because I cannot know who I really is (as DaveC pointed out too) -- is it really some unique/individual property of me and only mine, or is it perhaps a sophisticated computer program "pretending" to be an individual, thus, experience of "I am" is not really true, but false, and second, I cannot know that I am really doing the "thinking process" in a true sense as we now understand it, or it is something else making me think I am thinking.

    What I can be absolutely certain about is only "amness" -- now, what exactly is causing amness, awareness and beingness (either it is really me, a computer program, God playing humans, or whatever) is not the question right now, but simply what can "I/we" be certain about.

    IMO, that I am doing the thinking is not absolute certainty, but experiencing amness (existence of something) IS.

    I've never seen anyone say what I've said, which is simply put:

    1) I am.

    2) Existence must be eternal, or else I could never exist.

    3) Supreme beings must of have evolved, given eternity.

    But of course, I am open to the possibility of being wrong.

    No matter, I'd still like you to consider my 2nd and 3rd statements. (I am sure I'll find value in your sharing, either is it agreeing with me or not.)

    So, how possible is it in your view that supreme beings have evolved (something we might consider alike Gods - perhaps not in the classical sense of being all-powerful, but more in the sense of having very high level of awareness and love, so to say), since existence (of something) has to be eternal, or nothing would ever exist...
    Last edited: Feb 16, 2010
  20. Feb 16, 2010 #19
    Yes, I think, therefore I know I exist.
    Don't get caught up with 'I think therefore i am', its a translation.
    Cogito Ergo Sum does not define the "I". What you really are... is an ontological question.

    So they are two different things. Its not really relevant to what Descartes was talking about.
    Again, it doesn't matter what is doing the 'thinking', all that matters is that 'thinking exists', and by thinking you know that thinking exists, so it is self evident.
    All you have done here is lump together thinking and existing together into one concept. You are certainly free to do so, but it neglects the point Descartes was making, it doesn't address it.
    Sounds similar to buddhism... and various other eastern styles of mystical traditions.

    1) Again this is uninteresting from an ontological point of view, its merely a statement of fact.
    2) I see no reason this should be true, but I find the word 'eternal' doesn't have much meaning either.
    3) I think you misunderstand what 'evolution' means. Evolution is about adaptation to circumstance, not attaining any sort of perfection. And as to, supreme beings, supernatural god things are invariably vague and self-contradictory... theologies are generally more trouble than they are worth, at least, to philosophers. Fiction writers can get lots of use from them.
  21. Feb 16, 2010 #20
    1) I am.
    2) Existence must be eternal, or else I could never exist.
    3) Supreme beings must of have evolved, given eternity.

    To the I am part... Call me in thirty million years and say the same thing.
    To the existence must be eternal part... If it must be eternal then how did it start?
    To the supreme evolved part... I don't think I understand what you mean by evolved.

    Asking if other exist has to be about as bad as asking if someone you'v met on the street is god.
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