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Newton's Laws and a Supreme Being

  1. Jan 30, 2010 #1
    Personally I'm on the border-line between atheist and agnostic however the following statement gets me thinking. It is a statement that every physicist can resite without having to think;

    "Every object remains in a state of rest or in uniform motion until acted on by an external force"
    -Isaac Newton's First law of motion.

    Might this statement suggest that a supreme being exists or existed?
  2. jcsd
  3. Jan 30, 2010 #2


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    What would make you think that? The words "external force"?
  4. Jan 30, 2010 #3
    Well let's say I push a ball with my hand, the external force that caused that ball to move would have been caused by me. In the question, I am asking if Newton's Law prove to a certain extent that a force must have had to exist to in order for motion to exist. If there was no force at the beginning of time then there would be no motion, nothing would move. The statement also suggest that there had to be a beginning and that the belief that universe had no beginning or no end is false. If the universe had no beginning then there would be no motion.
  5. Jan 30, 2010 #4
    Also, don't forget that all of our theoretical formulations always are approximate to some degree; and there really doesn't seem to be any way of getting around it. So, though classical mechanics works very well in a range of circumstance (large scale cosmology not being included) it isn't strictly true.

    If questions of the history and potential beginning of the universe could be answered by employing logical deduction based on Newtonian physics they would have been settled long ago.
    Last edited: Jan 30, 2010
  6. Jan 30, 2010 #5


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    You're reading way too much into that statement.
  7. Jan 30, 2010 #6
    Newton certainly did not think so. He thought of his law as purely empirical.

    One might ask the same question about Aristotle's law of motion: "Every object remains in a state of rest unless acted on by an external force"
  8. Jan 30, 2010 #7
    I agree with Pengwuino, you are looking far too deeply into the statement. You could put evidence of a supreme being in any statement.

    "Where's the beef?" It is not beef that is missing, it is the supreme being. One must look past the metaphorical beef and search for inner protein.
  9. Jan 30, 2010 #8
    Now that I think about your question I see that Newton's Law must have lead to the question of how did it all get wound up in the first place. You seem to be stating this as how did forces emerge to disturb uniform motion. This must have been external to the uniformly moving bodies.

    Newton's Law does seem to say that any form of change must come from something external.
  10. Jan 30, 2010 #9


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    "Something external" isn't necessarily a supreme being, it just means another object(s) separate from the one that is observed to have a change in velocity. There is no supreme being implied here.
  11. Jan 30, 2010 #10
    True. But still you have to believe that the question of who wound up the great mechanism came out of Newton's Physics.
  12. Jan 30, 2010 #11


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    Well, no, I don't. People believed in God long before Newton came along.
  13. Jan 30, 2010 #12
    That's not what I meant. I mean given the Newtonian view that the Universe is a huge mechanism - accepting that - people then wondered how the mechanism , a new concept - got wound up in the first place.

    The idea that God would have set a great machine in motion then stood back and let blind laws take over must have been thought provoking.
  14. Jan 30, 2010 #13
    I don't see how proposing an unseen undefined uncaused causer provokes any thought.
  15. Jan 30, 2010 #14
    In those days I don't think it was a proposal. God was seen as real without question and not undefined. His method of intervention in the Universe and his concept of design was challenged and changed. Today we don't care about all of that. But Newton was certainly aware of it.
  16. Jan 30, 2010 #15


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    Why would you assume the universe started in an "unwound" state? Isn't that just as arbitrary as assuming it started in a "wound" state, which would negate the need for a creator?
  17. Jan 30, 2010 #16
    You are right. But in those days the wind up was necessary since God preceded and created the Universe. For us this is a dubious assumption. In Newton's day it was virtually undisputed.

    The question was not whether God designed the Universe but how.
    Last edited: Jan 30, 2010
  18. Jan 30, 2010 #17

    Ivan Seeking

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    Couldn't stand it, eh? :biggrin:
  19. Jan 30, 2010 #18
    All newton is saying is that if the net force on an object isn't zero then the object will begin to accelerate. His law says nothing about a supreme being.
  20. Jan 31, 2010 #19
    Ok, maybe the word 'supreme being' was the wrong chose of wording. And I'm not trying to suggest that 'external force' has anything mystical about it. My question is more surrounding the grander scheme of things and refers more to the beginning of time rather than the present.

    You see according to newton's axioms an object cannot move until a force acts upon it, such as if I were to kick a ball; I am exerting a force on the ball making it accelerate and move. I'm not well experienced in physics yet but I am sure that principle is the same even at the Quantum mechanical level (???).

    Now given that motion actually exists, we can move, the planets move, the stars move, the galaxies move, doesn't that suggest that a 'force' had to put those objects motion in the first place. I am not suggesting that a force still exists which makes these objects move but something (according to Newton's laws) had to put them into motion. If this never happened then shouldn't everything in the universe be at rest (not moving) or in a state of constant speed (which every object in the universe isn't)?
  21. Jan 31, 2010 #20
    http://en.wikipedia.org/wiki/Primum_movens" [Broken]is the phrase you are looking for.

    Problem, if a first cause exists, then not everything needs a cause, so your rationale for having a 'first' cause dissolves. There could be many things that don't require a cause. Gods unto infinity.

    Also, being at rest, is really a relative thing. There is essentially nothing different between being at rest, and being at a constant speed. Its change of speed that implies something has happened.
    Last edited by a moderator: May 4, 2017
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