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How is change possible?

  1. Sep 2, 2011 #1
    IN https://www.physicsforums.com/showthread.php?t=525749" thread a question was asked.

    “Why is there Something rather than Nothing”

    For there something to come out from nothing - or whatever the case may be - is required the concept of change.

    You may have heard in philosophy, panta rei or 'You can't step into the same river twice.".
    So, how is change possible? And, if this isn't the ultimate question, then what is?
     
    Last edited by a moderator: Apr 26, 2017
  2. jcsd
  3. Sep 2, 2011 #2
    Both change and the lack of change are relative to the observer like so many other properties. As for the ultimate question, "What is the gift of a question?" works for me.
     
  4. Sep 2, 2011 #3
    Yes, but we digress from here. Such as, "If 'change' is observer-dependant then what counts as an observer?" or more trivially, "If change is observer-dependant, then what is change?". It's cheating.
     
  5. Sep 2, 2011 #4
    What counts as an observer or change depends on the context like any other word.
     
  6. Sep 2, 2011 #5

    apeiron

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    How is stasis possible? Why does anything persist?
     
  7. Sep 2, 2011 #6
    Half joking, my ultimate question: Who are you?
     
  8. Sep 2, 2011 #7
    I'm talking about change not things being changed.
     
  9. Sep 2, 2011 #8
    Not fair. First answer my question.
     
  10. Sep 2, 2011 #9
    Show me a single definition of change that doesn't involve things.
     
  11. Sep 2, 2011 #10
    The original question posted a poem which can be understood to be a definition of change.
     
  12. Sep 2, 2011 #11
    Even the poem describes change in terms of things.
     
  13. Sep 2, 2011 #12

    apeiron

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    It is the same question. The water flows but the river persists. If you mean to draw attention to this standard Greek metaphysical question, then you have to consider the whole of it like they did.

    http://plato.stanford.edu/entries/heraclitus/#UniOpp ........

     
  14. Sep 2, 2011 #13
    See but it doesn't make sense if everything changes.
     
  15. Sep 2, 2011 #14
    How so?

    Ok. So, how do opposites exist if they cannot be identified?
     
  16. Sep 2, 2011 #15

    apeiron

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    How do things change if things persist? How do things persist if there is change?

    What do you mean? Your question identified them - stasis and flux, stability and change.
     
  17. Sep 2, 2011 #16
    Ok, identify a state of stasis as opposed to flux and I'll concede.
     
  18. Sep 2, 2011 #17

    It is again a question of context. The broader and more vague the context the less meaning and sense it conveys. Everything is "energy" or whatever makes no sense whatsoever because the context is simply too vague. You might as well say everything is spiffy or shiny.
     
  19. Sep 2, 2011 #18
    There seems to be no context in this case, since everything changes.
     
  20. Sep 2, 2011 #19

    apeiron

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    What does that mean? Any state of stasis would be opposed to one of flux.
     
  21. Sep 2, 2011 #20

    apeiron

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    But not everything changes at the same rate - again the river vs its waters.
     
  22. Sep 2, 2011 #21
    Hmm, that's not how I interpret it. But, another argument, in an ontological debate the general (Greek) rule is to drop all assumptions and study that what is left.

    Panta rei, all/everything flows or moves, to me means that he means the sensory (what else is there) observation that all perceived seems to be in a state of flux. And the question is, how can that be?

    Is the question whether there are things relevant for answering the original question?
     
  23. Sep 2, 2011 #22
    Ok ok. Your telling me how to spot change when it happens. But, why does it happen? What enables its happening?
     
  24. Sep 2, 2011 #23
    The context is "everything" and it patently defies human observation. As far as anyone can tell things like the laws of physics don't change so without a more specific definition it amounts to nothing more then mystical mumbo jumbo. That's not to say such things as mystical mumbo jumbo aren't valuable, but that they have no demonstrable value outside specific contexts.
     
  25. Sep 2, 2011 #24

    Astronuc

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    df/dx or df/dt,

    ∂f/∂x or ∂f/∂t,

    or

    Δf/Δx or Δf/Δt

    or simply dx, dt, ∂x, ∂t, Δx, Δt

    There is a difference, and change usually involves time.

    Coins and smaller denominations of paper currency are another possibility.
     
  26. Sep 2, 2011 #25
    Heraclitus closely resembles what is sometimes called "Energetic Taoism" and their motto is "change is the only constant". In specific contexts it can be a valuable approach to problems, but taken outside of any clear context it is so much obvious mystical mumbo jumbo that contradicts itself.
     
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