APA 2014-5: On the Reality of Atoms and Subatomic Particles

Silicium-atomesby Massimo Pigliucci

This is going to be my last report from the 2014 meetings of the Eastern Division of the American Philosophical Association. Obviously, it has been a rather idiosyncratic set of choices, reflecting my own interests, not necessarily the (much) broader scope of the meeting. Now if I could only convince some of my other colleagues to publish similar commentaries — including here at Scientia Salon — covering their specific interests in science and philosophy…

At any rate, this session was chaired by Otávio Bueno (University of Miami), and the speakers were Bueno himself and Jody Azzouni (Tufts University). Indeed, this was a strange, but welcome, session, with only one paper, entitled “Reasons to Think That Atoms and Subatomic Particles Are Real vs When to Suspend Judgment about the Reality of Atoms and Subatomic Particles,” co-authored and kind of co-presented by a scientific realist (Azzouni) and a scientific anti-realist (Bueno). (The presentation was mostly by Bueno, occasionally humorously interrupted, or substantively supplemented, by commentary from Azzouni. It really was fun!)

So, consider a new scientific theory coming along and positing the existence of some unobservable entities. The standard realist argument is that if those objects do significant work within the theory, and the theory has compelling empirical evidence in its favor, then one should think of said objects as actually existing.

Bueno then introduced a distinction between thin and thick epistemic access: the first one involves only theoretical reasons for thinking of an entity as real; the second one requires some type of detection device or methodology to gather at the least indirect empirical evidence for the existence of the entity.

Of course, perceptual experiences are one kind, but not the only kind, of source of thick epistemic access. Think of transmission electron microscopes, for instance. What convinces us that an object — say a newly discovered sub-cellular organelle — is a real biological structure and not an artifact of preparation is that we can replicate the observation under a variety of conditions and with a variety of instruments, as in fact happened with the discovery of, for instance, ribosomes [1].

This is interesting, and I get the value of separating thick and thin epistemic access. However, it also seems to me that Bueno has significantly extended the categories of observables compared to the standard anti-realist position, which would confine them pretty much to macroscopic objects accessible by standard human senses. And in fact, Bueno did acknowledge that adopting a van Fraassen’s type of strict empiricism [2] about unobservables makes it difficult to make sense of actual scientific practice (e.g., in the 21st century we really should consider viruses to be observables, even though of course they cannot be seen with the naked eye).

Again, this strikes me as fundamentally right, but it is definitely moving anti-realism much closer to realism; then again, on the other side of the divide, Ladyman and Ross-style structural realism [3] has been moving realism closer to antirealism, so there.

Given the above, does the empiricist antirealist still have a line to draw between observables and unobservables? Bueno thinks so, and Azzouni, predictably, disagrees.

The example proffered by Bueno is that of the scanning tunneling microscope [4]: it generates a constant electrical current which is then used to scan a given object up and down. This doesn’t generate an image per se, only information about the object based on how its surface interferes with the electrical current. This information is then processed by computers to generate an image for human consumption. People these days claim that with this instrument we can “see” atoms, but this — according to the anti-realist — is definitely not the case, because the microscope does not actually provide thick epistemic access to the objects of interest. This is evident from the fact, for instance, that the raw data can be represented in a variety of ways, generating very different images. (The “image” accompanying this article is of silicon atoms on the surface of a crystal of silicon carbide, obtained by a scanning tunneling microscope.)

(Notice that the anti-realist here is obviously not saying that atoms don’t exist, only that an empiricist should suspend judgment about the ontology of the entity under study, because the microscope, as sophisticated as it is, does not actually provide anything like images, so that we cannot properly talk about “observables.” Also notice that the anti-realist is perfectly aware of the fact that the distinction between observables and unobservables pertains to human epistemic access to the world, and it doesn’t cut the world at its joints, so to speak. But both realism and anti-realism are epistemic positions in philosophy of science, not metaphysical ones.)

A rather colorful way to think about the situation is that some instruments generate “public hallucinations,” analogous to rainbows: we can all see rainbows, and they have objective existence in the sense that we can describe them and even measure some of their characteristics, but that doesn’t mean there is an actual object out there that corresponds to the visual concept of “rainbow.”

Another interesting case concerns macroscopic objects, like the quest for detecting extrasolar planets. The standard method involves the application of a combination of Newtonian physics and relativistic corrections to infer the existence of an extrasolar planet from the wobbling of a given star. The technique has undergone very fast and very impressive refinements over the past few years, leading to the discovery of more and more, smaller and smaller extrasolar planets [5]. The thick epistemic access here is to the behavior of the star, not the characteristics of the planet (about which we have instead thin epistemic access).

The basic point is that thinking in terms of thick vs thin epistemic access gives the philosopher a tool to wade through cases where there is ontological disagreement stemming from the positing of unobservables in scientific theories, until (and if) they are eventually resolved empirically (e.g., ether: doesn’t exist; genes: do exist and they are made of nucleic acids). This leads to a more reasonable form of empiricism — anti-realism, which does justice to actual scientific practice while still retaining caution when it comes to ontological claims (van Fraassen’s famous goal of avoiding “inflationary” metaphysics in philosophy of science). I am certainly looking forward to seeing the published version of Bueno and Azzouni’s paper!


Massimo Pigliucci is a biologist and philosopher at the City University of New York. His main interests are in the philosophy of science and pseudoscience. He is the editor-in-chief of Scientia Salon, and his latest book (co-edited with Maarten Boudry) is Philosophy of Pseudoscience: Reconsidering the Demarcation Problem (Chicago Press).

[1] Ribosome, Wiki entry.

[2] Constructive Empiricism, by B. Monton and C. Mohler, Stanford Encyclopedia of Philosophy, 2012.

[3] Structural Realism, by J. Ladyman, 2014.

[4] Scanning tunneling microscope, Wiki entry. See also this animation explaining the tunneling effect.

[5] The Extrasolar Planets Encyclopedia.


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57 replies

  1. Like Dennett he writes from the psychological perspective or your brain doesn’t work the way you folk psychologists think it works. Dennett talks about the perceived stable image as a patch work of flicker fusion and Graziano states the medieval problem of white light perceived as pure light and a major point of his theory is about the tempo parietal junction and social awareness. Of course like Dennett we’re still left with the empty dish of “It’s all just neurons”. However explaining things in deeper terms of specialized structures in the brain gives the educated layman who reads the NY Times and the book it reviews more insight. Their books and reviews are edited and promoted by the publishers and promoted by the NY Times for popular consumption so they do need to be understood in that context. Yes I get a lot more out of reading their on-line papers. The books are just starting points.


  2. Imzasirf commented “I never fully understand why there is a debate between scientific realist and anti-realist because I never felt like the two perspectives actually make a difference in terms of the practice of science and perhaps not even in it’s implications.”

    Daniel, you say that metaphysics, epistemology, and definitions can be important. Okay, fine, but you are still not addressing his point. Why is there this debate, and what difference does it make?

    If it makes a difference to the practice of science or its implications, tell us what it is. If not, then admit that there are no scientific implications, but explain what difference it makes to philosophy, because Imzasirt questioned that as well.

    I can agree that there is value in clarifying definitions of words like “fitness”, but is that what we are doing here? I doubt that the realist and anti-realist philosophers would not be happy saying that they are just debating the definition of “atom”, with no scientific implications.

    I intended to replace the word “twaddle” with a less inflammatory word. Imagine that I used some more appropriate word, whatever that would be. I still don’t see why it makes a difference whether ribosomes are seen with an optical or scanning tunneling microscope.

    As for my “unsupported default view”, I would be happy to support everything I say. But I see that SciSal has announced a shift towards promoting the views of academic philosophers, and my PhD is not in philosophy. Regardless of my views, it is reasonable for Imzasirf to ask what difference this issue makes.


  3. schlafly, the new direction of SciSal (which isn’t that new, as I will explain in my forthcoming response to readers on that thread) will not affect comment threads at all.


  4. “Bueno then introduced a distinction between thin and thick epistemic access: ….”

    Well, I am here writing this comment. If anyone argues for the anti-realism on the ontological level, I have no desire to converse with him. I don’t think that Bueno’s view is correct. The key is about the meanings of two terms: reality and empirical evidence.

    Reality is manifested in many tiers (vertical and horizontal). For epistemology, they can be classified into two classes: sensual realities and beyond-sensual realities.

    For any ‘beyond-sensual realities’, they can be ‘empirical’ sensed only via an artificial ‘instrument’ which is based on some laws of nature. As most of nature laws reside beyond the sensual world, they are postulated by human-theories. When some of these postulations are ‘linked’ to the sensual world via ‘predictions’ and test verifications, those verified postulations gain the status of ‘laws’, no longer as postulations. Then, these ‘laws’ can be used to constructed an epistemological ‘telescope’ (Epi-telescope) to probe the ‘beyond’ world further. Today, the neutrinos (totally beyond the sensual world) are the most important Epi-telescope.

    While Epi-telescope is constructed by ‘known’ laws, physics today uses many pseudo-telescope which is totally theory-based, a step away from the law-based. Although there is no empirical evidence contradicting to the Standard Model, it is ‘known’ as theoretical incomplete. The discovery of the new 126 Gev boson is totally theory based, as if the background ‘calculation’ were different then that boson would not have been seen. While I and most of other physicists do know that this background calculation is ‘correct’, we do ‘know’ that something is still beyond this SM-telescope.

    Thus, the Epi-telescope is not a good enough tool for the total (final) epistemology. I have long advocating an ‘anchor/pit’ endo-cast epistemological tool.

    All know laws or nature constants (verified theories or measurements) form a set of ‘anchors’.

    All clearly defined open issues (such as dark energy, dark matter with Planck data) form a set of anchor-pits.

    Then, these anchors and pits form an epistemological endo-cast which forms a ‘web’. If a theory is ‘outside’ of this web, it will most likely be wrong.

    The followings form a web.
    One, the anchors.
    Nature constants (the Cabibbo and Weinberg angles, Alpha, etc.)
    SM fermions
    Quantum principle, gravity, etc.

    Two, the anchor-pits.
    Dark energy and dark matter (Planck data)
    The connection among tiers {fundamental physics, math, human faculties (intelligence, consciousness, free will, etc.), high level manifestations (economics, politics, linguistics, etc.)}

    Now, can Higgs mechanism (HM) making contact to any of the above anchors (deriving …)? Can HM resolve any anchor-pits above?

    The answer for both questions are big “NO”. Thus, the HM is wrong, and this can be determined soon enough (in a decade). This is not a prediction but is knowledge, and I am marking it here as a historical witness.

    So, the current Epi-telescope is the thin-access while the anchor/pit endo-cast is the total access.


  5. Hello,

    I have a few questions/comments after reading.

    Firstly, is anti-realist science an offshoot of post-modernist thinking? Which one came first? They seem to be closely intertwined, in their doubting of everything that is not directly observably and empirically found to be fact.​

    Secondly, I would like to ask a clarification on the views of realist from an anti-realist point of view: technically, everything we “know” should be a result of thin epistemic observations, right? After all, we are not “seeing” or “feeling” objects. They are simply interacting with neurons in our body that create a projection in our minds, right? I understand that this is a materialist argument and is fundamentally flawed, but isn’t that the issue with the realist vs. anti-realist debate? There is a hard solipsism which makes both sides’ arguments moot, correct?


  6. “Now, can Higgs mechanism (HM) making contact to any of the above anchors (deriving …)? Can HM resolve any anchor-pits above?
    The answer for both questions are big “NO”. Thus, the HM is wrong, …”

    Without some solid evidences, the above statement is just talking talks. Here are two types of evidences.

    First, the passive evidences:
    One, two and a half years after the discovery the new boson, the ‘Higgs Mechanism’ is not verified. Nigel Lockyer (Fermilab director) posted a statement on April 24, 2014 at (http://www.quantumdiaries.org/2014/04/24/massive-thoughts/ ), saying, “As just about everyone now knows, the Higgs boson is integrally connected to the field that gives particles their mass. But the excitement of this discovery isn’t over; now we need to figure out how this actually works and whether it explains everything about how particles get their mass.”

    Two, Aidan Randle-Conde (an LHC insider) wrote (on November 29th, 2013), “We were not sure that the newly discovered particle (with 126 Gev) is a SM Higgs, see http://www.quantumdiaries.org/2013/11/29/higgs-convert/#comment-161360 .

    Second, the positive evidences:
    One, for making contacts with anchors (nature constants, SM fermions, Planck data, etc.), see http://tienzengong.wordpress.com/2014/12/27/the-certainty-principle/

    Two, for filling up the anchor-pits:
    The 7-code model connects the math, physics, and bio-lives together. Yet, we can show that this 7-code is identical to the Real/Ghost symmetry (RGS). Then, this RGS further connects the fundamental physics with the high level expressions.

    Gravity: see http://www.prequark.org/Gravity.htm [Quantum spin (1/2 ħ) seeing two copies of universe (RGS) and it is ‘bouncing’ between the two. This bouncing gives rise to gravity.]

    Quantum principle: see http://prebabel.blogspot.com/2013/11/why-does-dark-energy-make-universe.html [This universe moves (expands) from HERE to NEXT with the quantum action ħ, and its governing force is F (space-time Force) = ħ/ (delta S x delta T)].

    Linguistics: see http://www.chinese-word-roots.org/cwr018.htm

    Math: http://www.prequark.org/Fermat.htm

    Economics and politics: links provided before.

    All these are the expressions of RGS (real/ghost symmetry, see https://scientiasalon.wordpress.com/2015/01/05/apa-2014-4-emergence-and-complex-systems/comment-page-1/#comment-10743).


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