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Dream or Reality

  1. Jan 23, 2006 #1
    I start in the beginning with Descartes' Cognito ergo sum. I think; therefore, I am.
    This, I think, is indisputable and proves that I exist, but where can I go from here using reason alone?

    I acquire verifiable knowledge that I previously did not know and had no way of knowing from sources outside myself. This proves to me that at least one other than I exists. I am not alone and have proved it to my satisfaction using reason alone.

    Example: I have a friend who comes from a town that I have never heard of. He gives me detailed directions how to get there and then to get to his home and its address. I follow his directions carefully and find the town just as he described it and fine his home with the address that he gave me. There I meet his mother and am invited inside. I see a picture of my friend on a table and his mother tells me details about my friend that I didn't know. I go back and see my friend and he verifies all that his mother told me.

    Thus, I have satisfactorily proved that not only does my friend exist but also does his mother and the world at least as far as that town exists.

    But wait a minute, Suppose that it is all a dream put in my head by Descartes' evil demon. I haven't proved anything except that I and at least the demon exists. How can I get beyond this point using reason alone?

    Let's try a thought experiment.

    Given infinite time and resources, I can, in principle, read an infinite number of books and talk to an infinite number of people other than myself, gaining infinite knowledge of the world and reality from sources other than myself and verify every detail of all of this knowledge.

    But, this does not prove that this is not a demon induced dream. If the demon/God is omniscient, all knowing, then he/she/it would be able to put this dream of infinite knowledge gained outside of myself into my mind.

    Given, in principle, infinite knowledge of all of reality and the dream of infinite knowledge of all of reality, there is no way to distinguish between the two. There is no way, by reason alone, that I could determine if it is real or if it is all a dream.

    If reality and the dream are completely indistinguishable in every aspect and detail then there can be no way to tell them apart. This is the definition of an identity, I.E. the dream is reality; reality is the dream.

    Now I apply Oakum's Razor. If they, the dream and reality, are indistinguishable in every respect and detail then one of the terms is redundant and superfluous. Whether we do away with the dream or reality makes no difference; but, since the demon and his dream are a figment of my imagination and cannot be verified to have independent existence, I choose, by reason, to do away with the demon and his dream and choose, instead, to believe in reality as verified by experience and observation.

    I believe that by this reasoning that I have finally been able to go beyond "Cognito ergo sum" and by reason alone prove the existence of others, the world and reality.

    Any comments? Is my logic and reasoning faulty? If so, where and can you suggest a way to improve it.
  2. jcsd
  3. Jan 23, 2006 #2


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    That might be a satisfactory argument against solipsism for all practical purposes, but strictly speaking it's no proof against solipsism.

    Consider your identity argument: there is no way for you to distinguish between the possibilities that your world is objective, or is a demon induced dream. But just because the two are indistinguishable to you, it doesn't necessarily they are actually identical. You might be able to say something like "they might as well be identical to me, so I shouldn't waste more time worrying about it," but you can't really conclude they are identical. Obviously, if there exists a demon-induced dreamworld on one hand and an objective world on the other, the two are not identical simply by hypothesis, even if they might appear identical or indistinguishable to a particular kind of observor.

    Occam's Razor, too, is more a useful heuristic than an ironclad tool of logic. My worldview will be more elegant (and I will feel much more sane) if I deny that invisible fairies track my every move, but this in itself is no proof that said fairies do not exist.
  4. Jan 24, 2006 #3
    You, of course, have pointed out the weakest point of my argument; however, in the thought experiment I stipulated "given infinite time and resources" I would be able to verify every aspect and detail of the dream.
    Yet I would never, even with infinite knowledge be able to tell whether what I knew and experienced was a dream or objective reality.

    It is not comparing one to the other for there is only one. What I experience and observe can be a dream OR objective reality and there is no way to tell which nor nothing to compare it too. I, also, would not be able to verify whether the demon exists or not or whether objective reality is real or a dream.

    As there is only on reality that I experience it is an identity and indeterminable whether it is real or a dream.

    As well with dream inducing demons. I choose objective reality because the demon exists only in my and Descartes' imagination and is no where objectively observable or verifiable. I presume that if my reality where a demon induced dream then demon(s) would exist in the dream but that is not necessarily so. A really clever tricky evil demon would never let himself be detected.

    There is still no way to prove objective reality and disprove solipsism or the other way around. However, I have reasoned (by making a reasonable choice. The demon is a possibility but not a reasonable one.) my way off of the "isolated island" that Descartes put us on. Descartes is accused of using circular reasoning to get himself beyond "Cognito ergo sum." I don't believe than my reasoning is circular but it may be.

    By the way what started me thinking about this again is I just started reading the book "Think" by Simon Blackburn. In chapter 1 entitled "Knowledge" he started with Descartes Meditations.
  5. Jan 24, 2006 #4
    i was going to bring up a point that might aid your argument,
    i lack the refence to give you a name, but to combat the saying that everything is a figment of my imagination, a philosopher once said: suppose i kick a rock. it hurts. it does not matter whether it is imagination nor reality. they hold the dame principles. in this case pain
  6. Jan 25, 2006 #5
    When I watched "The Matrix", I observed that there was no way for one to "prove" to himself that he was living in a program. Yet as he was given such knowledge to verify with his own 5 sences, the reality he was experiencing, in my understanding at that time, was another program in which neither he nor the creators of his first experienced reality could prove unless again given such knowledge with which to verify. To me, it could go on forever.

    If life were a dream, and we died and went to what we believe to be "heaven", would we accept heaven as reality and life as the dream? Could it be that heaven was simply another dream in which a higher reality existed?

    So if you proved that you were in a dream and you figured out how to "wake up" live in what had to be reality, you would again have to prove that reality to yourself.
  7. Jan 25, 2006 #6
    Not only that but you can never have only two choices.
    No matter how much knowledge, infinite or not, you have, there will always be more than 2 options to choose from.
    You say it all comes down to "hard cold reality vs solipsism", but in reality this isn't the case.

    There is a third option, and that option is "we don't know it", but it's still an option because once we get more than one option, then there will always be an incosistency, and that inconcistency is that we don't know which option is correct.
    Once that is in place, we can never be truly sure that there isn't another third option, or a fourth option even.

    So basically saying that it comes down to demon induced reality vs objective reality is false imo.
  8. Jan 25, 2006 #7
    When one believes that they experienced a "dream", or "objective reality", that confirms that the individual perceived an action or set of actions.

    Also, the fact that the individual currently thinks about the past-that which happened and was the thought about the dream or reality, precludes the possibility of that individual actually being in reality.

    So long as one thinks that the action or set of actions was real, whether or not they were derived from a "dream" or "reality", that one is destined for extinction.

    It wasn't about the story, despite the fact that it was highly touted and promoted and experienced, it always was about the moral of the story, and not every story had a moral.

    All that mattered was that one learned from the experience, placed another pebble on the pile of still-knowledge garnered from perceived actions, and has since jettisoned the memory of the "experience".

    Break karma.
    Last edited: Jan 25, 2006
  9. Jan 27, 2006 #8
    The only percieved "flaw" I have is that your Example does not prove the demon exists. I think your example on it's own is a beautifuly worded rationalle for your existance being real, reguardless of the controlling force, if any.
  10. Jan 28, 2006 #9
    I don't think that the demon is important. What is important is whether the reality that I perceive and experience is a "dream", all in my head, or is it objective reality, really real as I experience and believe it to be. I have no way of telling or proving which is which. I do think that the dream is unreasonable and requires something or someone extra to put this elaborate and detailed dream in my mind.
  11. Jan 28, 2006 #10
    I was going to add something to my comment shortly after I wrote it, but I wanted to think on it some more. Sometimes when reading peoples posts I get struck by how profound and intelligent some peoples opinions are. This was one of them. I deemed it worthy of being given more deeper thought. After doing some thought about your test I was trying to determine whether it was "circular" logic.

    I started to look at it as whether our "waking life" was real. As opposed to our "dreaming life". I guess I never really asked myself why we sleep/dream in the first place. (I don't know if that makes me an idiot or I just took it for granted all these years). What then dawned on me is that if we didn't dream, perhaps we would have no real reason to question reality in the first place. There would be no other thing to compare it to. This is what you failed to mention in your expiriment. Is whether or not, given infinite time to gain infinite knowledge, you slept. Only if you had dreamt would you be able to determine a difference between your two "waking life" choices. You have sufficiently proven that you and I are living in the same plane of existance in what I have determined to be my "waking life". So I asked myself, "Who cares who is responsible for our waking life, who is responsible for our dreaming one?"
    Last edited: Jan 28, 2006
  12. Jan 28, 2006 #11
    There is a propensity to turn our minds inside out and impose solely human attributes on to reality. I use a definition for reality which helps me to keep the two differentiated. I define reality as that which exists apart from anything that I wish, hope or fear that it might be until such time as I am able to physically make it other than what it is. Reality does not respond in any significant way to what I believe it to be and the burden of proof I place on what reality ‘actually’ is, is whether my beliefs can be logically (conceptually) substantiated based on perceptual data. This requires practice in its application but I know of no other route to any degree of certainty.

    Can dreams exist apart from the dreamer and the waking experiences that lend themselves to the dream? Choose to believe this to be true at your own risk but I am overwhelmed by evidence to the contrary.
  13. Jan 28, 2006 #12
    you can't physically make me change my mind, you can however still convince me to change it with data. So my mind must not exist. whether or not my actual mind might be just a chemical reaction do completely benign things. Whatever the cause, I'm thankful to whomever/whatever/however it came to be that I have the ability to dream. Even a mathematical equation. "Thank you hypothetical math equation!!!!" It's such a cool property of conciousness. Can we agree on that?
  14. Jan 28, 2006 #13
    Just in case there is any confusion about my previous statement I do not question the reality of the existence and potential value of dreams, either the waking or sleeping variety.
    I see evidence here that your mind does exist, though I am at somewhat of a loss to evaluate its state. Maths, to say the least, is not my forte but what knowledge I do have is that it involves, in a high degree, the use of logic. I give thanks to the many who have come before me who have discovered the rules of logic that I apply in using my humble ability to reason. This “!!!!” leads me to believe that you value your existence enough to put forth some effort to maintain it. I would agree that this is an essential attribute for thinking rationally.
  15. Jan 28, 2006 #14
    I appreciate your concern for my sanity. I am both sane and rational. Just had an "a-ha" moment that keeps me interested in the subject. Some subject matter discussed in these forums can be somewhat dry and boring, (especially to a layman). Just thought someone might apreciate that it can be exciting and lead to greater self-awareness. To actually go out and learn about things instead of taking other peoples words for it.
  16. Jan 30, 2006 #15
    Thank You for not taking my word for anything other than my point of view unless and until you can verify any correlation to reality it might have, based on your own experience. Such verification is essential to maintaining any value it may have had in the offering.
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