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Does plurality exist?

  1. Jan 15, 2005 #1
    Does plurality exist or is everything 1 'thing'?

    (im not sure if plurality is the right word, maybe 'multiplicity'?)

    For instance:

    6 billion humans - the human race
    many grains of sand - a beach

    And if u slice a human body into 2 parts, does that make it 2 bodies?
  2. jcsd
  3. Jan 15, 2005 #2
    Anwsering your question regarding if you slice a body in 2 parts...

    If you slice a body in half you do not have two bodies but rather 2 halves of a body.

    Lets just say that:

    a = b
    0.5a does not equeal to b! Simple!
  4. Jan 15, 2005 #3


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    I am pretty sure a sandpile exists as a thing, not just as a collection of grains. Tha angle of slope of the pile is an emergent quality, that cannot be attributed to any particular combination of grains, but only to the whole. Even one grain extra can cause it to slump.

    Philosophers differ though, about human society. Libertarians tend to say with Mrs. Thatcher, there are no classes, there are just individuals.

    But this ignores the fact thet mob behavior, for example, is different from individual human behavior. Emergence does exist in human society too.
  5. Jan 15, 2005 #4
    Thats true
    but then
    0.5a + 0.5a = b

    So it really remains a single thing.
  6. Jan 15, 2005 #5
    Hey, selfAdjoint. Long time :smile:.

    I agree with your quote, and add only that it is the realization of such a synergy (if you'll excuse the term) that allows for some of the more important discoveries of the last century (viz. Nash's "Governing Dynamics", Rorty's "Epistemological Behaviorism").

    Your question is one of the oldest and (IMHO) most interesting ones of philosophy. Parmenides put forward the idea that all things were "one" and static; change and plurality are mistaken terms. The Eleatics followed suit (Zeno, being the most famous among them).

    After David Hume, empiricist Solipsism could be taken as a different form of the same concept, in that all things could be the "impressions" and "ideas" of a singular mind. Kant added the difference between "concept" and "intuition" in order to escape that, but it's still a valid question (that is, if one follows the philosophical paradigm-shift of Descartes and Locke, and thus has a representationalist bias a priori).

    As for my own opinion on the matter, I'd say that plurality does exist physically, but not always linguistically. Take your own example: if a human body is sliced in two, is it now two "bodies"? Well, no, but it is two seperate entities, physically speaking. In terms of the linguistic puzzle, I think it's better to simply say that there has ceased being a "human body" at all, and, in its place, are now two blobs of flesh that, for reasons of social and linguistic convention, cannot accurately be called "human".
  7. Jan 15, 2005 #6
    Thanks for the info :)

    But about your last bit where you say things can be seperate entities, physically speaking:

    Suppose you have your own body and you grab an apple. What really is the difference between your hand and the apple? Are they somehow attached to eachother(on the smallest level perhaps).

    Or even if there is an open space(of air) between you and the apple, is there some kind of connection between your body and the apple?
  8. Jan 15, 2005 #7
    First of all Pit2 your logic does make sence. It is true that 0.5a+0.5a = b


    0.5a DOES NOT EQUEAL b. It does not matter whether the two peices make a whole what matters is that half of a whole is not a whole!

    In a physical sence there is no attraction between the apple and the hand, only repulsion from the electrons charges from the apple and hand.
  9. Jan 16, 2005 #8
    Where you choose to make the dividing lines between objects is a matter of convenience. "Emergent" properties are not added to what was there previously; they are simply the result of smaller properties, and you can look at the "sand heap" as those little particles or as the whole, whichever is more expedient to compute with; if you do it perfectly you get the same answer either way.
  10. Jan 16, 2005 #9


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    In pure theory maybe. In the physicist's dream reductionism works, and everything could be calculated from quarks and leptons. But even at the actual theoretical level the series don't always converge and approximations have to be used (Lattice QCD and such - look up perturbation theory). Emergence turns out to be a good way to look at many systems, or if you prefer a less be-new-aged term, critical phenomena.
    Last edited: Jan 16, 2005
  11. Jan 16, 2005 #10

    Now, consider the following statements:

    (a) 3.5 people are in the room

    (b) John is tall

    (c) I am an approximation of a real human

    (d) Mankind is preserved

    These are just a few of very odd statments purporting to be conveying facts about the world. Can you prove that they are right or wrong?
  12. Jan 16, 2005 #11
    There are holes in your illustration, if taken directly, but I think I get what you mean: If two bodies are connected by anything (even air or empty (as much as the term "empty" has physical meaning) spacetime), then are they really two bodies? If so, what makes them such? Is that pretty much what you mean?

    I guess the only problem with that is whether you consider space a "connection" (and, if it is a plenum, as much classical philosophy would have you think (and as some of modern physical theory would allow), then a case could perhaps be made toward that end) or simply a relation between two points of reference.

    If, OTOH, you meant something else by your illustration, then please clarify :smile:.
  13. Jan 16, 2005 #12
    So perhaps quarks and leptons are not a perfect theory. It's all a matter of choosing a theory and using it. Any division between objects is within the theory. The theory, however, is not the physical world.

    In the instance of the sand pile, I think it would be harder to make a perfect simulation using the total idea of the pile than it would be using the concept of each grain in the pile. It would be easier to get a first approximation, but harder to do it perfectly.

    Simply because it is "more convenient" to calculate using one theory rather than another does not mean that the theoretical objects used to compute the theory are somehow real. All objects are invented by humans to make it easier for them to think.
  14. Jan 16, 2005 #13
    Yub, thats what i meant.
    You said yourself that 'empty' doesnt really have a physical meaning. So if there is no emptyness(or nothingness) then musnt everything be 1 thing?

    I wonder what you would see if you zoomed in infinitely far on matter, or empty space. Or better, what would be there without observing it.
  15. Jan 16, 2005 #14
    I cannot prove if those statements are right of wrong.

    But what is your point?
  16. Jan 16, 2005 #15
    I do not know what your thoughts are, and vice-versa. Therefore, we are two separate entities.
  17. Jan 16, 2005 #16
    You do not even know what your own thoughts are until a moment after you've thought them, and if I told you what I was thinking then you can know what I am thinking.

    When information about one system is not present in another system, this is not sufficient to fundamentally separate the two systems.
  18. Jan 17, 2005 #17
    "Must" is a strong word. It could be considered "one thing", then you'd have to deal with the philosophical puzzle of how it is that two people can disagree about whether it's "one thing" or not.

    Some of the candidates for ToE (Theory of Everything (are you familiar with the term, as used in physics?)) have proposed that space is quantized, so you could only "zoom in" so far, and you'd be looking at "chunks" of spacetime itself. As to matter, one these candidate theories (the superstring theory) posits that you would see one-dimensional "strings" of energy (these being the most fundamental of particles (i.e. electrons and quarks would not be points or ball-shaped particles, but vibrating "strings")).

    As to what's there when we're not observing it, philosophies differ greatly on this point. Some would say that nothing's there at all, until you look at it. According to the quantum mechanics, the very nature of particles (and spacetime) is probabilistic, and so what observations you can make when you "zoom in" on a particle are not the only true observations that can be made (IOW, if you observe a particle to be in a certain place, you have observed one of many "probable" locations of the particle).
  19. Jan 17, 2005 #18
    "A moment after you've thought them"...clarify please. Are you referring to thought as an event (with defined beginnings and ends, and final products)?

    But just the reference to them as "one system" and "another system" has semantically separated them (obscure pun intended).
  20. Jan 18, 2005 #19
    Yes. It is a computational convenience to deal with thought in this manner. Any action of the mind cannot be known by the mind--i.e., placed into the mind's short-term memory--until somewhat after the action happens.

    Humans may create all the semantic separations they like, for their computational convenience. None of these separations indicate any fundamental difference.

    Even if a theory of everything is created and satisfies all experiments that test it, and even if this theory of everything has a smallest theoretical element, the theory is still nothing more than a computational device. These "smallest theoretical elements" are only figments of the device, convenient to compute with but having no greater meaning than that.
  21. Jan 19, 2005 #20
    If there is more than one fundamental 'thing' then it becomes very difficult to explain how they both came into existence. After all we can't manage to explain one thing doing it, so to explain the odd coincidence of more than one thing doing it is a tall order. On the other hand it was argued by Leibnitz, and I feel he is correct, that something that is one thing cannot have physical extension.

    Take your pick. There's no answer that does not contradict the two-value logic that we normally call reason.
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