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What is reality not?

  1. Jan 12, 2008 #1
    In a previous thread I asked folk in this forum the question “What is reality?” and got a whole heap of interesting replies. An early reply that proved to be the most apt was

    In the end it sadly turned out (to misquote Omar Khayyáám’s Rubááiyáát) that :

    Myself when old did eagerly frequent
    Doctor and Saint, and heard great Argument
    About it and about: but evermore
    Came out by the same Door as in I went

    I have since concluded that I was asking the wrong question. Hence this thread. Perhaps those who know what philosophers think can comment here on what isn’t reality (whatever that is.....). To start with I list some items that seem to me to be in this category. I begin with obvious examples.

    First, the contents of:

    1. Dreams and nightmares.
    2. Myths, such as the cosmology of the Mundurucu folk in the Amazon basin
    3. Stories about Harry Potter

    Second, human constructs which have familiar and powerful physical representations, such as:

    5. Movies
    6. Music
    7. Money

    Third, everyday tools that seem to me to be part of the non-real Platonic world:

    8. The anti-eponymous “real” numbers
    9. Zero, infinity and negative numbers, and their arithmetic
    10. Imaginary numbers and complex analysis.

    Lastly, sophisticated systems of mathematics and physics that can serve to describe nature, like:

    11. Gibb’s vector algebra, formulated in about 1880, which quickly replaced the more clumsy mathematical descriptions of nature then in use.
    12. Geometric algebra that subsumes more specialised systems, such as Clifford and Cartan’s algebras
    13. General Relativity, which describes gravity better than Newton did, but leaves the nature of that "real" phenomenon, gravity, still as mysterious as ever.

    (If you adopt a solipsist approach and doubt the "reality" of gravity itself, try ignoring it. I advise you to start in a small way, say by ignoring the existence of the bottom step when next coming downstairs).
  2. jcsd
  3. Jan 12, 2008 #2
    Reality is not objective (in many senses).

    #1 Not objective because I don't think you will find total agreement for what this thread comes up with.

    #2 Because everyone's experience and belief systems are different.

    #3 Because we don't have a god's-eye view to sufficiently say what it is or is not. We are part of what reality* is, but can we look around from within and understand it wholly?

    #4 Despite your attempt to debase solipsism (which is a faulty traditional attack on the 'external' components of a solipsist's experience) -- solipsism remains ever irrefutable :rofl:

    * I was assuming 'reality' in the common sense understanding of the word. Of course this has the potential to break down with expanding #2 :D
    Last edited: Jan 12, 2008
  4. Jan 12, 2008 #3
    reality is perception
  5. Jan 12, 2008 #4
    If it matters then it's real; if it's not real then it doesn't matter.

    Just for completeness I might add: if it's real then it matters; if it doesn't matter, I'm not interested.
  6. Jan 12, 2008 #5
    reality is not real
  7. Jan 13, 2008 #6
    Thanks for your reply, singleton. I agree with pretty much all you say in your first three numbered points:
    But: because I hadn't got an understanding from a previous thread on what reality is, I'd hoped to get a better understanding --- by default, as it were --- of what it isn't. No success so far, I'm afraid.

    On your fourth point, namely:

    I do apologise. I couldn't resist the temptation to poke some fun at solipsism, which I regard as one of the strangest phoibles of philosophers. You are of course quite right - it is irrefutable ... but that doesn't prevent its being just plain silly!
  8. Jan 13, 2008 #7
    I take the OP to mean: fill in the blank with valid answers. "Reality is not _________." So with this in mind, I will submit

    #5. Reality is not changeable. This might be a little hard to defend. But if reality exists, and that is not necessarily a given, but if it does exist, one can assume that a person cannot go back and change it. One can change a lot of things, such as parameters, circumstances, direction, and so on, but within the arrow of time one cannot change reality.
  9. Jan 13, 2008 #8
    a pretty big question. since this is a science forum, can anyone prove that reality exists or not?
  10. Jan 13, 2008 #9
    "Real" and "existing" are interchangeable terms. If not then someone needs to explain what it could mean to have real things that don't exist or things that exist but aren't real...
  11. Jan 13, 2008 #10
    We have a knack to dismiss it as silly because it downright scares us to truly consider it and the implications. I used to be terrified of the concept and would get a panic attack just thinking about it.

    However it remains one of the most important concepts in philosophy (particularly epistemology). Scientists hate it as a wildcard because, as you would imagine, the non-believer of a theory can pull that card at any time... "How do you know what you observe is true....?" :rofl:

    It makes us feel damn uncomfortable, and we shun it as nonsense, but that doesn't help or justify to refute it anymore ;)
    Last edited: Jan 13, 2008
  12. Jan 13, 2008 #11
    Sure, solipsism is not refutable. Fortunately it's not relevant either. The external world may or may not exist as it seems, but whether it does or does not makes no difference because what matters is our perceptions. After all, if we could not perceive anything then nothing would matter.

    We create models to describe what we perceive, how and when we perceive it, and so on. We use these models to predict what we will perceive next so that we can support favorable perceptions and prevent unfavorable ones. If these models fail us, we drop them in favor of better ones. If these models work for us, it does not matter if they correspond to a "true reality of type X" or a "true reality of type Y". So as long as our models work and benefit our perceptions, it's of no significance if they are of some "true world" or only of our "true self alone in an otherwise empty universe". Whatever is real enough to affect us and our well-being is real enough for all purposes.
  13. Jan 13, 2008 #12
    Not relevant? That really depends on your perspective. I happen to think it is quite relevant for my life. It affects how I perceive the world and I think it has a large impact on how I live my life and questions of 'certainty' and 'truth'. My entire world view is hardly made up of my 'perceiving' alone -- reason, curiosity and other things inside of me are my main drive. If you do not care about anything outside the scope of your 'model' or window of thinking then I could appreciate how it is not relevant for you.

    I know it is very relevant to me not as a means or approach to life--I am not a solipsist --but the implications it has on my self-acknowledged limitations. (This is a philosophy sub-forum after all...)
  14. Jan 13, 2008 #13
    But when you apply your reason, curiosity and other things, you do so towards what you perceive because this is the only input you have (what you see or taste, how you feel, etc.) When you perceive that an object is falling, you become curious about this observation. You repeat experiments in order to obtain a greater number of perceptions. You reason that what you perceive can be described using concepts of force, mass and acceleration. A solipsist would reason that his perceived "inputs" are not external but somehow arises from within. Fine, they "somehow" arise and our model describes this "somehow" using concepts of force, mass and acceleration. The model works for the solipsist as well as for the non-solipsist, so it doesn't matter which point of view is adopted.

    The model is not the center of interest. We care about what affects us and therefore create a model to understand how we are affected. The true nature of reality is unknown, it is what we seek to understand and the reason why we create models. But being able to describe how things interact (creating a model) is not the same as knowing the true nature of reality, which can only be experienced through our perceptions. This puts perceptions at the center of what matters.

    How would your self-acknowledged limitations be altered if you discovered that your understanding of reality is the understanding of "unknown reality of type X" instead of "unknown reality of type Y"? You would still understand a finite number of concepts, still believe that you can run the distance you believe you can run, still interact the same way with what you perceive to be your mother, friend, pet, computer, etc.
  15. Jan 13, 2008 #14
    They can be used interchangeably, but they have different connotations. What is real is usually used in conjunction with experience... which is phenomenological. We can speak of virtual reality for instance. 'Existing' is more solidly ontological and may not have anything to do with experience. Plato(forms) and Kant(noumenon) both, for different reasons, could be said to have had non-phenomenological ideas of what exists.

    And that difference is a very old philosophical argument.
  16. Jan 13, 2008 #15
    Yes, I agree with that, but my post was in the context of this question: does reality exist? In this context, I think the question pretty much answers itself. If reality does not exist then is anyone even asking the question?
  17. Jan 13, 2008 #16
    Reality is not synonymous with the 'self'. Solipsism says that the self exists but the phenomena of experience are 'illusory'. So one could say that what we percieve as reality does not exist under those conditions. Just like virtual reality 'doesn't exist' in the way we normally use the word.

    As Descartes observed, the self pretty much takes care of itself... but what the limits are of the self... and how it relates to reality/existence thats a bit more murky.
  18. Jan 13, 2008 #17
    Could it be that: reality is that which is processed by the Observer and non-reality is that which is not?
  19. Jan 13, 2008 #18
    But under solipsism specifically, reality is indeed the self because the self is all there is. Our perceptions are just misinterpretations of this reality. Reality (the self) exists all the same. And of course outside the solipsist point of view, reality remains all there is.

    Sure, we can select specific definitions of the words in order to justify a claim that reality does not exist. But if what is meant is just that "things are not as they seem" then using these well-understood terms instead can save a lot of semantic debate.
  20. Jan 14, 2008 #19
    Oh, I see what you are saying now. I would have said from the solipsist point of view, that reality is 'within' the self, a part of the self, or a function of the self. But yes, I can see it the other way too, the self identified with reality.

    Unfortunately, in my experience 'well-understood' terms are the ones that cause the most problems in philosophical discussions. But yes, I think we are general agreement.
  21. Jan 14, 2008 #20
    If one accepts proof as a matter of probabilities, gauged with experience, then of course it is fair to talk of "reality existing", just as in a practical way one expects the sun to rise tomorrow. And I can't see how else to think of proof. One might be misled by experience sometimes, but probability based on the possibility of error takes care of this.

    There is of course proof based on logic, but when one listens to the maunderings of politicians, string theorists, theological pundits and even (dare I say it?) one or two philosophers, the possibility seeps in that even seemingly impeccable logic can be sometimes lead reason astray.

    It would help to know if others agree or disagree with what I judge to be "not real". There's nothing like fixing on examples to clarify your meaning.
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