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Why is matter hard to define?

  1. Sep 12, 2005 #1
    Care to venture ideas? i need some...
  2. jcsd
  3. Sep 12, 2005 #2


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    Because its behavior doesn't behave like the categories we derive from toddler physics and social interactions. There's no reason why it should, and it turns out it just doesn't.
  4. Sep 12, 2005 #3


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    In what ways do you think matter is hard to define?
  5. Sep 12, 2005 #4
    "Matter is anything with density."

    Why is that so hard to understand, unless i'm missing something?
  6. Sep 14, 2005 #5
    It depends on the definitions you use. For instance, what is density? The ratio of mass and volume (mass/volume = density). But wait, what is mass? One definition is "a measure of how much matter is in an object," which creates some problems to say the least. A similar thing happens when we try to define energy. What is energy? The classic definition is, "the capacity to do work." But wait, what is work? "The energy exerted in applying a force over a distance." Hmm, that too creates some circularity problems. (You can go to Merriam-Webster's dictionary and look up both energy definition 3 and work definition 2c if you want to verify my claims.) In reality, there is no fully satisfactory definition of energy (much like "life" in biology). The same might be true for matter.
  7. Sep 15, 2005 #6
    I agree, I dont think this answer will be achieved using a system such as english to describe the universe to the most fundamental level, atleast presently. I, for one, do not really believe we even have the ability to understand matter at the most fundamental level and truly grasp what it "is" for certain. It is just something that when probing deeper and deeper into, the more confused one seems to be. Just like one is to ask 'What exactly is time?' It just can't be done within the universe. Wait until you leave this system someday and ask that question, it may be answerable. But would it then even matter? If it does not matter, why are we concerned about it now. Here we go again. Circularity problems.
  8. Sep 16, 2005 #7
    There is no matter, nothing is solid. Everything is just forms of thoughts and energy. When you punch a wall, your hand is not even touching the wall. Nothing solid is actually striking each other. Its electromagnetic forces repelling when they get close. What we perceive as a small Nuclei, protons and neutrons rotating around and when they are just about to hit, their electromagnetic force repells each other, and nothing actually touches. Then we go to even say there are smaller particles than that, that dont even touch. So there is nothing really solid about us. We are very thin gas with forces. How can you ask a fish to explain water? Fish arnt smart enough, and neither are humans.
  9. Sep 16, 2005 #8
    I'm not sure I 100% agree with you on that one. I do agree that electromagnetic forces are the main constituent of why, for example, I do not "go through" the very chair I'm sitting in and go right into the center of the earth. Because the gravitational force acting on my body is almost infinitesimally smaller (something like a billion, billion times smaller) than the electromagnetic forces that are acting also. Thus, theoretically if someone could "punch" hard enough there could be actual collision. However, that is well beyond what any human can do for sure. But a certain older experiment tells me otherwise, with the gold foil and shooting alpha particles at the thin gold foil. The alpha particles would "bounce" off only when hitting the dense nucleus of the atom. And I strongly disbelieve they were opposite charges. I think in that experiment there was actual collision. But if not, correct me.

    Also, what about particle acceleraters? They send particles without opposite charges hurling at near the speed of light and collide and they precisely measure what occurs and how they "break apart" into their smaller constituents. That does not seem like repulsion to me.

    The whole idea of everything in the universe not having any kind of solid constituent kind of strikes me as illogical. I do realize a major percentage of all the universe is actual empty space, but I also have come to realize that if there is always more space "in" what we define as matter, than matter itself is an illusion and all of our phyics would be misconceived. The amount of matter or mass of an entity would then just turn into the volume that an entity displaces, but how is an entity to displace nothing if they are composed of nothing. Just seems illogical. But maybe you meant something else by it.
    Last edited: Sep 16, 2005
  10. Sep 16, 2005 #9
    Well, science tells us that we have a good estimate or idea of what 'Matter' is. In philosophy nearly 99.99% of the time is devoted to defining things. That is, finding the exact or perfect definition of a given term of reality. The whole project is turned on its head when we turn philosophisical attention to Metaphysics - a branch of philosophy which questions the fundamental nature of things, relations and quantities. When hair-splitting questions such as (1) what things really exist?, (2) what categories of things are there?, (3) what relations do things really maintain between them, given that we know what things exist in the first place?, and so on, here your guess is as good as anyone else's.

    The problem about definition of matter is one thing, and the problem of reducing matter to other things is another. What I mean is that you added more headache to the problem, for it seems that to reduce matter to ever smaller layers of things, we ought to first know what it really is. So, you see the problem just get bigger. Unless you are inviting us to accept the Problem of definintion and the problem of reductionism to be one and the same thing. Are they?
    Last edited: Sep 16, 2005
  11. Sep 17, 2005 #10
    Trying to understand metaphysical problems in philosophy always ends up questioning more fundamental assumptions as it proceeds. Why "understand" more or less ? Why use any form of logic ? What exactly are we trying to reach ? These ideas go on forever and as you proceed you slowly take apart all thought processes, logic, reason, all intentions and you end up with everything and/or nothing. The end result is mostly aesthetic or artistic. Just invent arbitrarily anything etc.

    Philosophy has no given goal. It doesn't necessarily want to increase our understanding, some philosophers may want to decrease our understanding as "understanding" may not be such an interesting goal. Some philosophy likes the purely artistic view of things hence there is no relationship with science. Some philosophy likes to be completely wrong on everything because they are not using right and wrong concepts or non contradictions as taken for granted.

    Philosophy, in the wider sense, is very much more general and abstract than science, it questions every conceivable assumption, demolishes every conceivable logic and thought process. Real philosophy is truly non social and has no use whatsoever. It is this that makes it so much grander than science.
  12. Sep 17, 2005 #11
    I would submit that no collision takes place, at least not in the physical sense. What azneternity may be trying to get across is that matter is composed of nothing at all, that on the fundamental level all constituents are no more than geometrical embodiments (conceptual entities).

    One might just as well say that the breaking apart is the result of close proximity (still no collision).

    On the contrary we have no proof of solid constituency unless you are prepared to show solid constituents on the fundamental level, and last I heard no such animal exist. This leaves the possibility of non-physical open for discussion.
    Empty space to me is as busy as any other location in the universe. Matter to me is the location of the foci of fundamental geometric entities, space is merely the extension of those foci.
    Mass - The kind that is no more than a geometric embodiment of nothing at all, does not displace anything. This is because all of nothing is shared. If the universe is descibe as a non-physical entity, one must throw displacement out the window in favor of conceptual understandings. In other words - If the universe is not a physical entity.............Physics cannot be used to explain it.

    I would submit that the universe is a conceptual geometric embodiment of nothing at all. We cannot make physical from nothing.........only conceptual.

    In our universe there are only ones, one at a time, where time is the nothing ones are composed of.
  13. Sep 17, 2005 #12


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    There obviously is matter. Consider the definition that first pops up on dictionary.com:

    So the concept of matter is not crucially dependent on the concept of solidity, and matter does indeed exist.

    The more interesting question is, "What is the nature of matter?" Here is where objections about solidity and the like come in, and I think these are disguised ways of objecting to natural folk concepts of matter as a substance, e.g. matter as made out of some kind of 'stuff.' It does appear that physical theory requires no such commitment to the substance view of matter; rather, matter is described purely in functional terms, in relation to other physical entities and forces. So matter may not be a kind of 'thing' so much as a kind of property or disposition (or a grouping of such properties) to act or interact with other functional entities in certain kinds of characteristic ways.
  14. Sep 27, 2005 #13
    From Einstein, we know that matter can be defined in words as "energy divided by speed of light squared" (M = E / c^2). This seems like a very direct and useful definition of matter. From this we see that matter must in fact exist, otherwise neither would energy exist, for we cannot have energy that is not matter moving very fast indeed.
  15. Oct 2, 2005 #14
    Thanks you guys, that was helpful.
  16. Oct 2, 2005 #15

    Les Sleeth

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