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Would anything exist if mankind - the observer/participator - wasn't around to see

  1. Apr 15, 2008 #1
    Would anything exist if mankind -- the observer/participator -- wasn't around to see

    I was reading Wheelers Obituary in the Los Angeles Times. A passage in the obituary piqued my mind. What do the forumites have to say?
  2. jcsd
  3. Apr 15, 2008 #2
    This is an interesting question, and one I can see both side of.

    The first thing that comes to mind when I hear this though is that obviously things would happen if mankind wasn't around to see it, because obviously events had to occur in order for the earth to develop into a place in which mankind could live on. Considering we weren't around when the Earth was molten (or even at the point of the creation of the universe), we can infer that things do occur and exist even if we aren't around, otherwise our universe itself wouldn't exist, let alone Earth.
  4. Apr 15, 2008 #3
    You're digging deep into philosophy and metaphysics... :wink:

    My personal belief is that nature needs us (and all living creatures) to be witnesses of the existance (of everything).

    Kind of evolution of that conviction back when I was a kid that the world would cease to exist each time I closed my eyes. :biggrin:
  5. Apr 15, 2008 #4
    Yes. I concur this borders on metaphysics. The question which is the subject of this thread was raised by Wheeler. I had trouble deciding whether it belongs in the philosophy forum or the cosmology forum. There is a fine line since much of cosmology is theory that is yet to be proven.

    I understand your premise in that without us, being all living things, there is no nature as we know it.
  6. Apr 15, 2008 #5
    I would say that there is a fine line between philosophy and science in general. Well, both are products of our minds and therefore are opinable.
  7. Apr 16, 2008 #6


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    A more relevant question, perhaps, is if the laws of the universe are inherent or imposed. Does the existence of observers force the universe to behave logically, or is it a limitation the universe imposes upon us? Perhaps we are prisoners of our own logic.
  8. Apr 16, 2008 #7
    That sounds like Gödel's Incompleteness Theorem extended to the whole universe... :biggrin:
  9. Apr 16, 2008 #8
    So we may never know the real truth.
  10. Apr 16, 2008 #9
    How about "we WILL never know the real truth?" :wink:
  11. Apr 16, 2008 #10
    Yes Daiquiri, I concur, with Godel's incompleteness we will never know more than the one who created us or from whence we came, i.e: The Universe. But Godel's logic is based on basic answers to questions like True or False. Aren't we more complicated than that? I said may because we seem to be uncovering more secrets as time goes by but as to if we will hit a critical mass where we can't find out anymore and we will reach the limits of our intelligence and knowledge over time. I don't know.

    I read your bio. I see your an aerospace engineer in Brescia, Italy. I am an aerospace engineer in Los Angeles, CA. I am also of Italian ancestory. Its a pleasure to talk with you on this forum.
  12. Apr 17, 2008 #11


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    I like Daiquiri's version. Godel has a powerful argument, IMO.
  13. Apr 21, 2008 #12


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    Did something exist before humans existed?
    If not, how did we came to be as if it did?

    Answer. Yes, things exist even if no one is watching (why wouldn't they?).
  14. Apr 22, 2008 #13
    Sorry, I was absent from the forum for some time. The pleasure is mine, though I'm actually not italian. :smile:
  15. Apr 22, 2008 #14
    Based on what evidence?
  16. Apr 22, 2008 #15
    Here's a poem i once read in a quantum physics book,

    There once was a man who said, 'God

    must think it exceedingly odd

    if he finds that this tree

    continues to be

    when there's no one about in the quad.

    Dear sir, your astonishments odd

    I am always about in the quad

    and that's why the tree

    will continue to be

    since observed by, yours faithfully, God
  17. Apr 22, 2008 #16
    Since observed, but not before observed. Before observing it, we have no proof of it's existance. After we have observed it we create our logical models (which need to be proved, and that's where Godel jumps in and spoils everything) which can tell us whether it will exist after we cease our observation.

    Now you could say that we can demonstrate it's existance from an indirect observation, i.e. by observing the effects of it's interactions with the ambient. In the dark, for example, we can sense it's perfume, or we can hear the noise of it's leafs waving in the wind.
    Well, that's not a proof. You have once again constructed a logical model which correlates the effect to the cause, but any model can be confuted.

    Note that all the world as we know it is a model created by our organism and our mind from the very moment a photon hits our retin or a soundwave bounces off our tympanic membrane.

    And, by the way, in my view maybe the tree is not the right subject to argue upon, since it is a biological organism made of cells which can sense (and therefore can observe, in a way) the surrounding ambient and react to external inputs.
    In other words, maybe a tree is an observer - just like us... :wink:
    Last edited: Apr 22, 2008
  18. Apr 22, 2008 #17
    But surely that is no proof that it didn't exist before we observed it
  19. Apr 22, 2008 #18
    Imagine yourself in a completely dark room (no photons),
    a visible light source in the room flashes on/off once.
    The photons leave the light source and after a certain amount of time they hit, say an apple. Then some of them reflect off the apple and hit our retina, we have observed the apple. But the apple must have been there before we observed it because the photons were reflected BEFORE they entered our retina.
  20. Apr 22, 2008 #19
    And is there a proof that it did exist before we observed it?

    Please note that I've never said that things don't exist if we are not watching them. What I've said is that we have no proof of their existance if we are not able to observe them.

    Your affirmation quoted above is demonstrating the same thing, but from other way round.
  21. Apr 22, 2008 #20
    The flaw in your demonstration lies in the fact that you are putting yourself in a privileged position, where you know what happened before that photon hit observer's retina.

    The observer doesn't know what happened, he only has the information carried by that photon. Based on that single information he has to use his physical models to explain how and why did that photon hit his retina.
    And not necessarily his conclusion needs to be that there is an apple in the room.

    A physical model cannot be taken as a proof of the existance of that apple. The answers it gives are valid only within the limits of validity of the model itself.
    Last edited: Apr 22, 2008
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