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  • Eddington's tables

    Once in a while I get in to a discussion, which I sometimes regret but often not, with people on planes or trains about what I do. Here's an example of a puzzle I think about, with some analysis below the fold if you want to think about it without any help:

    The example comes from Arthur Eddington, a famous British physicist of the early 20th century. Consider the table in front of you. Physics tells us that it's really a bunch of charge properties over various fields of force. Common sense tells us that it's this solid thing upon which our computers sit. Are these two pictures compatible with one another? Here's an argument:

    1. Tables are fundamentally complex systems ultimately composed of charges and fields of forces. (Scientific realism)
    2. Properties that we perceive like color and solidity are not logically entailed by properties of charge and fields of force. (Anti-reductionism)
    3. Tables have properties we perceive like color and solidity. (Common sense)
    4. The only properties complex systems have are the logical consequence of the properties of its ultimate constituents. (Anti-emergence)

    Premises 1 and 4 imply
    5. The only properties a table has are the logical consequence of the properties of its ultimate constituents.

    Premises 3 and 5 imply
    6. The table's "every day" properties like color and solidity are logical consequences of the properties of its ultimate constituents.

    But notice 6 contradicts 2. So, since this is a valid argument, we know that 1-4 form an inconsistent set: at least one of those statements is false. But which one(s)?


























    --------------------------------------------------------------------------
    There are basically four options for resolving the puzzle: we can reject premise 1, reject premise 2, reject premise 3, or reject premise 4. These come in two general flavors. We can deny one of the pictures, either the scientific picture or the common sense picture. Or we can try to rethink the relationship between the two pictures. Here are the options:

    Reject premise 1: Scientific realism is the thesis that scientific claims are to be taken literally as claims about what the universe is like. We might reject this idea and take scientific claims to be metaphors or heuristics, perhaps in the way that statistics talks about the average American having 2.2 kids. Nobody thinks there's such thing as the average American or 2.2 kids. That's just some kind of device to summarize a lot of information, not to be taken literally. By rejecting premise 1, we can resolve the puzzle by saying charges and fields of forces aren't literally real.

    Physicist Richard Feynman seems to have thought something like this at one point. He says, in Surely you're joking, Mr. Feynman! (which by the way I highly recommend reading), "The electron is
    a theory that we use; it is so useful in understanding the way nature works that we
    can almost call it real..." It seems here Feynman is implying that he doesn't think the theory of physics literally describes some particle in the universe.

    Still, it seems really hard these days to deny that physics is telling us about how the universe literally is.

    Reject premise 3: On this solution, our everyday talk of tables is only talk of how they appear to us and not how they actually are. This is to say that there really is no such thing as color or solidity. Those are only illusions of the mind, to be placed in the same category as ghosts, hallucinations, phlogiston, or any of the other many things that we thought were real but turned out illusory. But to say that there really are no colors or that there is no solidity is pretty anti-common sense.

    Now on to the strategies of rethinking the relationship between the two pictures.
    Reject premise 2: To reject this premise is to hold that reductionism is possible in science. Reductionism is the view that there are bridge laws which logically connect the atomic features of the table to its everyday features. But what could they be? Nobody knows how to formulate them or even how to go about attempting to find them out.

    Reject premise 4: Scientists are hopeful that a single theory about the universe at a fundamental level will be able to explain everything about how the universe works. To reject premise 4 is to reject that idea, by accepting emergence. Emergence is the notion that some properties can arise within a complex system without there being an explanation why it happens.

    Which one will it be?

  • #2
    Re: Eddington's tables

    Reject premise 1
    It's extremely difficult, if not impossible for the average person to truly resolve a mental image of an atom.
    If you ask them, a lot of people will immediately pull out some variation of Bohr's, and while handy for learning the concepts, it doesn't accurately describe the system. Then alternatively, you use quantum mechanics to describe that atom more accurately...and people's eyes glaze over and their brains short-circuit.

    The models and equations we've been able to develop are undoubtedly quite fantastic and beautiful but ultimately, they're just that--models and equations.

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    • #3
      Re: Eddington's tables

      Originally posted by Flarfignuggen View Post
      It's extremely difficult, if not impossible for the average person to truly resolve a mental image of an atom.
      If you ask them, a lot of people will immediately pull out some variation of Bohr's, and while handy for learning the concepts, it doesn't accurately describe the system. Then alternatively, you use quantum mechanics to describe that atom more accurately...and people's eyes glaze over and their brains short-circuit.

      The models and equations we've been able to develop are undoubtedly quite fantastic and beautiful but ultimately, they're just that--models and equations.
      Well rejecting premise 1 has nothing to do with how the average person understands physics. Scientific realism is not a thesis about how well we understand what science says. Scientific realism is the thesis that our fundamental scientific findings are attempts at literally describing how the universe is - regardless of whether the actual person can understand those attempts or not. A rejection of scientific realism treats science necessarily as a discipline that doesn't literally tell us about the universe. On this anti-realism view, notions of charge, fields of force, fundamental particles, atoms, and the like are all just heuristics, metaphors, or useful fictions that scientists use to communicate some information about the universe. The universe doesn't literally contain any of those things on this view.

      Given what you say, I'm not sure you recognize the full import of rejecting premise 1. The view resulting in the rejection of premise 1 is more extreme than I think you may be thinking. If you think that the things physicist describe, atoms, electrons, charges, and fields of force, literally exist - regardless of how well you fully understand those things - then you're a scientific realist.

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      • #4
        Re: Eddington's tables

        Topics like these emphatically remind me of my stature in the world as one of the "unwashed masses".

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        • #5
          Re: Eddington's tables

          It's okay if you're one of them. Topics like these are fun to think about even for those who have no technical scientific knowledge. That's because it's meta-science, or the philosophy of science. It's a puzzle scientists face, an important one since a correct understanding of the nature of science depends on the correct answer to the puzzle, which they can't generally answer using scientific methods.

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          • #6
            Re: Eddington's tables

            Originally posted by sordavie View Post
            Given what you say, I'm not sure you recognize the full import of rejecting premise 1.
            Rereading it makes me agree with you. I think my position is more closely aligned with rejecting the principle of "common sense". "Common sense" and our macroscopic projections of the world around us has less to do with accurately describing the world and more with not making our brains invert on themselves.

            Don't remember where I read it but I seem to recall a line about how what humans really don't need is a truly good sense of scale [in response to the size of the universe, on either end of the scale].

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            • #7
              Re: Eddington's tables

              The common sense view might be a bit more extreme than you envision too. To reject premise 3 is to reject the existence of tables, chairs, trees, computers, and any other object we appear to believe on an everyday level. Fundamental physics says nothing about the existence of these things. The view that results in rejecting premise 3 takes tables, chairs, tree, computers, bricks, and so on to be mere useful fictions, metaphors, or heuristics, not to be taken for literal existence. It also seems pretty extreme to me to deny common sense like this. But again, it's not a matter of how well we understand these things. If you believe that the objects we believe ourselves to typically interact with on an everyday basis like tables literally exist, then you don't deny premise 3.

              Do you believe that you exist? ;) After all, humans are objects of common sense, not described as one of the entities of fundamental physics. It's quite hard to deny that you exist or to deny that the computer you're typing on exists.

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              • #8
                Re: Eddington's tables

                I'd reject premise 2. I might be misunderstanding the sentence below, but I think that the things about an object that we see and feel (colour, hard/softness, etc.) are directly because of the properties and interactions of their constituent particles.

                2. Properties that we perceive like color and solidity are not logically entailed by properties of charge and fields of force. (Anti-reductionism)
                |TG-Irr| westyfield

                Sig pic by Sonic, avatar by Chalcas. Thanks!
                Irregular since 2007.

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                • #9
                  Re: Eddington's tables

                  I wouldn't really say I'm denying its [the table's] existence, just the validity of our human perceptions in describing it. If you were to take the "common sense" side of describing the table as a solid object, you would miss out on atoms being almost entirely empty space.

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                  • #10
                    Re: Eddington's tables

                    Originally posted by westyfield View Post
                    I'd reject premise 2. I might be misunderstanding the sentence below, but I think that the things about an object that we see and feel (colour, hard/softness, etc.) are directly because of the properties and interactions of their constituent particles.
                    Premise 2 is the claim that properties like color and solidity are not logically entailed by properties of charge and fields of forces. Historically, scientists had been optimistic that they would be able to find what are called bridge laws. These bridge laws would tell us how color and solidity are logically entailed by properties of charge and fields of force. The idea here is that the phenomena we experience everyday can be logically reduced in a lawful manner to phenomena at the fundamental level. Unfortunately, since the 1950s scientists have backed away from this reductionist program and are more circumspect. Nobody knows how to go about figuring out what the bridge laws are, if there are any.

                    It's not clear whether you reject premise 2 or premise 4. You say that you think properties like color and solidity are directly due to the underlying fundamental properties of charge and fields of forces. But you don't specify what the "directly due to" part is. If you think it's due to bridge laws that make the former logically entail the latter, then yes, you reject premise 2. If you think it's not bridge laws, then what? One thing you might say is that properties like color and solidity are instantiated due to properties of charge and fields or force but for no reason at all. This is a claim of emergence, and thus a rejection of premise 4. Emergence says that some properties can appear when some other more fundamental properties are arranged in a certain way, but for no lawful reason. It just happens, like magic. Again, scientists are pretty weary about this kind of view.

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                    • #11
                      Re: Eddington's tables

                      Originally posted by Flarfignuggen View Post
                      I wouldn't really say I'm denying its [the table's] existence, just the validity of our human perceptions in describing it. If you were to take the "common sense" side of describing the table as a solid object, you would miss out on atoms being almost entirely empty space.
                      I'm not sure what you mean by 'validity' in this context. Notice that the puzzle paints us basically the existence of two tables: the scientific table (composed of charges and fields of force) and the common sense table (composed of color and solidity and the like). If what you mean by rejecting the validity of human perceptual descriptions, you mean to say that there are no such things as color and solidity, then you reject the existence of the common sense table. If you only mean that our perceptual descriptions are inaccurate or not complete but the common sense table does exist - that is colors and solidity and the like are genuine properties in the world - then you don't hold a strong enough position to reject premise 3.

                      Again the puzzle is that there genuinely are two separate descriptions of the table that can be treated like describing two different tables. So we can think about rejecting premises 1 and 3 as rejecting the existence off one table or the other. It sounds like you actually reject one of the other premises, since it seems you want to admit the existence of colors, solidity, and other common sense properties while also admitting the existence of charges and fields of force, all as genuine constituents of the universe. That is, you don't appear to want to reject the existence of either table. In order to stave off the contradiction, if you want to hold on to these, you need to deny either the anti-reductionism premise or anti-emergence premise. In short you need to either hold that common sense properties can be logically reduced to charges and fields of force, or you need to hold that common sense properties are emergent (they are somehow grounded on but for no lawful explanation at all) from charges and fields of force.

                      Comment


                      • #12
                        Re: Eddington's tables

                        I should probably say that I don't have an answer to the puzzle. I'm not sure which premise is most plausible to reject. And of course there is no consensus amongst philosophers or scientists who think they do know how best to resolve it. Though I take it there is consensus that it is a genuine puzzle, though some won't admit it's a puzzle since they think the answer is obvious.

                        Some days I think maybe rejecting premise 3 is the best way to go. An error theory could explain why we still use ordinary every day talk. It's all literally false, but it communicates some pragmatic intentions and it helps us get around in the world. But then I realize that implies rejecting the existence of life, as well as persons. And if you reject the existence of persons, then you reject your own existence. It's a rejection of all morality. And so on. On this view, the universe contains only charges and fields of force - that's it. That's a pretty extreme view. My dissertation adviser holds this view, and I criticize various aspects of it all the time.

                        Other days I think maybe rejecting premise 1 is the best way to go. After all, who's actually seen a gluon? Nobody. And a graviton? What the heck is that? That must just be some shorthand of mental metaphor for understanding various parts of the mathematical equations these scientists are using. Science on this view is just a heuristic. But then I think to myself, what the heck do I know of science? I'm no expert. Scientists tell me that they've literally discovered the existence of these things, and it's not just a convenient or useful fiction or metaphor. I should probably take their word for it, as I have no great evidence against what they say.

                        Still other days I think there must be some lawful explanation of everyday phenomena to fundamental physical phenomena. But then I think of how horribly we've actually failed to do that. There are a few problems here. First, science doesn't have the methods to do this. It requires doing some philosophy. But it's not even clear what philosophical methods will get us the answer. Most philosophers of mind these days have given up on the idea that mental properties, like consciousness, reduce to physical properties, like neurochemical activity in the nervous system, by some physical laws. These philosophers are partial to the emergence view of the mind. And what would the physical laws explaining how moral properties like rightness, wrongness, goodness, and badness are logically entailed by charge and fields of force even look like?

                        Of course on days where I read about quantum mechanics, the notion of emergence becomes salient. On some interpretations of quantum mechanics certain things can happen for no reason at all. When I say no reason at all, I mean genuinely no reason at all in principle - not just no apparent-to-us reason. So if these theoretical physicists are right about their interpretation of the theory, then we should believe in emergence. But of course it's quite hard to believe that some nonfundamental stuff happens for no reason at all. We don't like to believe that. String theory for instance is an attempt to explain why certain things that appear to happen for no reason at all on those interpretations of quantum mechanics actually happen for a reason. As scientists, we're always optimistic that we can explain anything that's not at the fundamental level by way of fundamental level phenomena. It's unsettling to think that some things can happen by magic (and by magic I mean without in principle any underlying explanation, not even God or an omniscient being could tell you why).

                        Moreover, in the end, which everyone you think feels best to reject, you also have to back it up with evidence. And that evidence is hard to come by. Intuitions count as evidence in my book, but it's very very weak evidence, easily defeasible. We need more than that.
                        Last edited by sordavie; 05-22-2011, 06:06 PM.

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                        • #13
                          Re: Eddington's tables

                          Originally posted by sordavie View Post
                          It's not clear whether you reject premise 2 or premise 4. You say that you think properties like color and solidity are directly due to the underlying fundamental properties of charge and fields of forces. But you don't specify what the "directly due to" part is. If you think it's due to bridge laws that make the former logically entail the latter, then yes, you reject premise 2.
                          To clarify, yes, bridge laws are what I'd go with, and reject premise 2. I don't have any decent justification for this other than that I don't particularly like the idea of macro-scale things happening for no discernible reason. If my desk's solidity is simply emergent, then what's to stop it suddenly becoming soft? I don't want my monitor to fall onto my feet, it's heavy!
                          |TG-Irr| westyfield

                          Sig pic by Sonic, avatar by Chalcas. Thanks!
                          Irregular since 2007.

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                          • #14
                            Re: Eddington's tables

                            Get on discovering those bridge laws!

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                            • #15
                              Re: Eddington's tables

                              There are problems with each of the 4.

                              1. We have a very good idea of how the physical world works, but not a perfect one. Plus our good ideas are limited to what we can detect and what we can deduce with our limited minds.

                              2 and 3 Our perceptions are just that, perceptions. They are determined by the structure of the brain. We know this to be true because people have parts of their brains destroyed and they no longer perceive things the same way. Some people are born such that they don't see colour. We could all be born that way so it is a chance of nature that we see color. It is possible that we may have evolved such that we didn't perceive solids. Don't know how we we could have evolved that way but I think it is possible.

                              4. Really kinda related to the problems 2 and 3. Emergence is a consequence of our methods of observation and limited ability to comprehend the whole from the parts.


                              I don't see a conflict between emergence and reductionism. They are one in the same.
                              Iím not racists, I have republican friends. Radio show host.
                              - "The essence of tyranny is the denial of complexity". -Jacob Burkhardt
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