Jaegwon Kim's Case Against a Science of Pain

On epiphenomenalism? The Korean-American philosopher argued that pain isn’t a “scientific kind”. He didn’t also argue that people don’t feel pain.

Symbols:

N = a particular neural state

P = a particular pain

W = a particular wince

Causal Overdetermination?

The philosopher Jaegwon Kim (1934–2019) argued that a particular neural state (symbolised N) is what he called the “supervenience base” of my toothache.

I winced (W) because of my toothache (P).

What caused that wince?

Surely it must have been the pain that caused me to wince. Jaegwon Kim, on the other hand, believed that it’s a particular neural state that caused me to wince. More radically, as Kim himself put it, N is “causally sufficient for wincing”.

So was there a difference between the neural state N and the experience of the toothache?

If N and P are two different (as it were) things, then both N and P (the pain) might have caused me to wince. However, according to Kim, this would be a case of something being “causally overdetermined”.

Yet why does it automatically follow that if two things cause a third thing, that this third thing is causally overdetermined? That is, doesn’t it sometimes take two or more things to cause a third thing? In fact, can’t there can be very many causal conditions which are required to bring about a particular effect?

A simple answer to the passage above is this:

If x is causally necessary and sufficient to bring about y, then x is all that’s required to bring about y.

Of course overdetermination has been widely discussed in philosophy. (For example, in the ontology of objects and in the philosophy of science.) However, Kim doesn’t got into detail on this. The following is probably the reason why.

If P and N are one and the same thing, then to say that both P and N (as separate phenomena) cause W is a case of overdetermination because… well, they’re the same thing. However, that’s not actually causal overdetermination: it’s thinking that one thing is two things. Thus, in actual fact, there’s no genuine overdetermination at all here.

In any case, there’s an alternative to this possible overdetermination which involves a three-way journey from N to the wincing.

We can have a chain from N to P… and then to W. Yet Kim says that N and P are perfectly simultaneous. There’s no causal journey from N to P because they occur at one and the same time…

… But do they?

It’s indeed the case that human cognition can’t register the time-lapse between N and P; though that doesn’t mean that there is no time-lapse. The interval may be milliseconds or less. And even if only a millisecond, that would still have constituted a temporal and “causal gap” between N and P.

Kim completely rejects this causal gap. Indeed he doesn’t even discuss the possibility that it may exist. Instead, he argues that P “supervenes on” (or is “realised by”) a neural state: it’s “not caused by” N.

Thus, in Kim’s eyes, supervenience isn’t a relation of causation.

When argued argued that P supervenes on N, then that didn’t also mean that N causes P. It simply meant that P supervenes on N…

But what exactly does that mean?

Can such supervenience occur without causation? But if it does, then how and why is that the case? And if this applies to the relation between N and P, then does it also apply to all mental states and their supervenience-bases?

For example, say I formed a mental image of Johnny Depp. That means that I can’t say that neural or (brain state) N caused my mental image of Depp. All I can say is that the mental image supervenes on a particular neural state…

Though, again, what exactly does that mean?

So what plays the main “causal role” when it comes to my wincing? Is it N or P?

What is the Causal Role of Pain?

If N doesn’t cause P (i.e., if P supervenes on N), then perhaps that question doesn’t make sense. Perhaps both N and P caused W. However, Kim has just argued that this is a case of overdetermination. And, if that’s the case, then wouldn’t that mean that Kim wanted to (somehow) get rid of pain (or get rid of this specific P, e.g., my toothache)?

Kim couldn’t get rid of N because there’d be no pain without a neural state. So could he get rid of the pain itself? Surely not. Would I have winced without a (mental) pain? Of course not… surely.

Kim, at a prima facie level, didn’t seem to want to get rid of P. Or at least he wrote that “if we trace the causal chain backward from the wincing, we are likely to reach N first, not the pain”. Indeed he continued by arguing that it’s

“incoherent to think that the pain somehow directly, without an intervening chain of physiological processes, acted on certain muscles, causing them to contract; that would be telekinesis, a strange form of action at a distance!”.

This seems to be a denial that something that’s purely mental can act on the physical. Or, at the least, it’s a argument that the mental can only act on the physical if the mental is itself physical. (Or, in this case, if the mental supervenes on the physical.) So Kim rejected what can be seen as the Cartesian or dualist position. Indeed Kim argued that something purely mental acting on the physical (in this case, on muscles) would be like “telekinesis” or “action at a distance”. The only way out of that would be to see the mental and physical as one — otherwise we would indeed have telekinesis or action at a distance.

Again, it must now be said that Kim didn’t reject either pain or the mental generally. Instead, he argued that

“if the pain is to have a causal role, it must somehow ride piggyback on the causal chain from N to the wincing”.

[We’d need to discover what exactly the words “pain riding piggyback on N” actually mean.]

As stated, Kim firmly rejected what he called the overdetermination that is “two independent causal paths”. That would be a path from N to the wincing and another path from P to the wincing”. The simple way out is to see N and P as one.

But how can a neural state and pain be as one?

This was the position adopted by the old-style identity theorists (or “type physicalists”) of the 1950s and 1960s. The main difference with Kim, it seems, is the introduction of the notion of supervenience. However, is the notion of supervenience satisfactory and/or acceptable?

In any case, one obvious conclusion to all this is to argue that P is epiphenomenal. And that’s what Kim did argue.

Is Pain Epiphenomenal?

Is there a difference between the following? -

(1) P supervenes on N.

(2) P is epiphenomenal.

In other words, if P is truly epiphenomenal, then it is (to use Kim’s words) “wrong to think of pain as a causal effect of N”? In fact earlier in the paper, Kim himself cited an analogical case. He referred to the shadows of a moving car. He wrote:

“The shadows are caused by the moving car but have no effect on the car’s motion. Nor are the shadows at different instants causally connected [].”

And then Kim compared the car’s shadows with someone’s toothache. He continued:

“Similarly, you may think that the pain in your tooth has caused your desire to take aspirin, but that, according to epiphenomenalism, would be a mistake: Your toothache and your desire for aspirin are both caused by brain events, which themselves may be causally connected, but the two mental events are not related as cause to effect any more than two successive car shadows.”

So if all that’s the case, then what purpose does the pain actually serve? After all, according to Kim, it’s

“[b]eing real and having causal powers go hand in hand; to deprive the mental of causal potency is in effect to deprive it of its reality”.

[The problems with the view above is that it would make numbers, past events, propositions, etc. unreal too.]

Indeed without the pain working as a genuine cause, aren’t we talking here about a simple mechanical cause and effect without the interaction of any kind of mentality? If the actual tooth… ache, in this instance, has no causal role, then what role does it play?

Reductionism or Eliminativism?

Jaegwon Kim’s solution to all this seems to be reductionism. Or at least he puts the reductionist position when he says that the “reductionist identifies pain with neural state N”.

In another paper, Kim did argue that pain as a “scientific kind [] must go” and that reduction is the answer.

Pain — at least as a scientific kind — must go primarily because (in Kim’s case at least) of the problems associated with the multiple realizability of mental kinds in many and various physical substrates. This is what Kim himself wrote on that subject:

“[T]he frank acknowledgement that MR [multiple realizability] leads to the conclusion that pain as a property or kind must go. Local reduction after all is reduction, and to be reduced is to be eliminated as an independent entity.”

As already stated, it’s clear that Kim accepted that pain and mental states (or qualities) exist: it’s just that he didn’t also deem them to be scientific kinds or properties.

However, when putting his case, Kim identified P with N — but with the addition of supervenience. (Unless, of course, such a reduction can exist side-by-side with supervenience.)

In any case, Kim happily finished off by arguing that

“reductionism has been rejected by the majority of philosophers of mind for what they take to be compelling reasons”.

References

Kim, Jaegwon, ‘Multiple realization and the metaphysics of reduction’ (1992)

• ‘Mental Causation’ (chapter 6) in his Philosophy of Mind (1996)

[I can be found on Twitter here.]

Kantian Experience in Contemporary Jargon

 

There are philosophers who claim that there's such a thing as “non-conceptual experience”. Christopher Peacocke, for example, says that there are experiences “with non-conceptual contents” (1992). That is, concepts don't wholly or partly determine all mental contents.

Perhaps Kant was correct about experience. He argued that we apply certain “a priori concepts” or “categories” automatically: i.e., non-cognitively. It can be added here that we may also apply non-Kantian contingent concepts in such a way. It may follow from this that there's no such thing as non-conceptual experience.

One may consequently ask what a baby experiences or sees. The Kantian “manifold”? Not according to Kant himself. The reason being that the baby’s “cognitive faculties” (in contemporary terms), or its “transcendental a priori structures” (in Kantian terms), are already determining the baby's experience of the world according to necessary concepts or categories.

The Kantian scheme is broadly correct; although we shouldn’t adhere too zealously to the letter.

Take this un-Kantian way of putting things.

The innate neurophysiological structures determine the mental concepts and the mental concepts (applied non-cognitively) determine both perceptual experience and linguistic categories (such as subject/object/substance, cause and effect, temporal sequence, spatial ordering etc.).

What if we aren’t a Kantian in the above sense?

Take the following as a piece of a priori theorising about the experiences of a baby.

Babies must have non-linguistic concepts and categories. That of an object and event for a start (this is still a Kantian position).

Take the mothers of babies.

Of course babies don’t at first use the word “mama”, for example; though they may well have a concept of the object they will later call “mama”. That is, mama is individuated, differentiated and perhaps identified (somehow) as the object that will be called “mama” in the future. Babies may even have non-linguistic conceptual criteria of identity for mama. Indeed they must have conceptual criteria of identity in order to individuate mama from, say, the chair on which she sits. They don’t, after all, smile at the chair.

So babies must have the concept [mamma] before they can use the name “mama” otherwise they couldn’t use “mama” to refer to mama. The word 'mama' itself doesn’t individuate mama. The word 'mama' refers as much to the concept [mama] as it does to the object mama. Without all this, there would be an object to the baby; though it wouldn’t be mama.

It may, of course, be difficult to accept non-linguistic conceptual criteria of identity. Can we make sense of non-linguistic concepts and criteria of identity (therefore, non-linguistic individuation)? Of course we can. Take the case of my parents’ dog.

This dog, Joe, knows who I am. It doesn’t have a language. How does it recognise me? By individuating me from other persons and objects by applying conceptual criteria of identity to the object humans call “Paul Murphy”. The possible conceptual criteria of identity Joe applies to Paul Murphy may be [a particular smell], [particular clothes], [facial features] and [a particular voice].

Joe, the dog, has also individuated and applied criteria of identity to events.

For example, (my) picking up the dog chain must be a specific individuated event for the dog. This event “means”, to Joe, that it will be going for a walk (itself an individuated event). Possible conceptual criteria of identity for the dog chain event for Joe could be [the noise of the dog chain], [my picking it up] and [my going into the hallway].

This is a quasi-Kantian position on experience. Kant himself, in his Prolegomena To Any Future Metaphysics, wrote:

“…concepts…under which every perception must be first of all subsumed and then by their means changed into experience.”

And elsewhere:

“…perception can never work as experience without the law that, wherever an event is observed, it is always referred to some antecedent…”

Kant’s passages are, of course, referring to a priori necessary concepts of experience (e.g. [cause-effect], [substance] [object], etc.), which are automatically or non-cognitively applied to sensations. But the passages could equally apply to a posteriori contingent concepts; which are also sometimes non-cognitively “applied” - though often cognitively applied too.

For example, I cognitively apply the new concept [lad] to a young man of a certain kind; though I don’t always cognitively apply the concept [crash] to a crash. Although the concept [crash] is a posteriori and contingent, a crash is an [event], which is a Kantian concept, and therefore a priori and necessary.

Jennifer Church writes:

“To those of us with Kantian sympathies…it seems that a state…cannot count as an ‘experience’…unless it is a certain way for, or to as a subject.” (1995)

This isn’t just a pedantic conceptual point that the word 'experience' means what Kant says it means. It's to say that there's no such thing as nonconceptual… whatever you want to call it.

One can take a quasi-Kantian position on experience without using Kant’s own terms or indeed philosophical terms at all. For example Michael Tye writes:

“…[in] very early vision…categorisations are automatic [non-cognitive]. They do not demand that the creature have beliefs or thoughts…” (Tye, 1990)

However, Tye goes on to say, about animals, that

“some…further categorizations…do so without the essential involvement of concepts (understood as involving a public language or thought…”

Surely Kantian a priori concepts wouldn’t need a “public language”; and neither would the kind of animal concepts acknowledged later.

Perhaps Tye precludes such “categorisations” as conceptual because they are “automatic”: i.e., non-cognitive and therefore a priori. Though there's no antecedent reason why concepts shouldn’t be automatic and non-cognitive. Indeed we even apply contingent non-Kantian concepts non-cognitively, such as the concept [crash], which is based on the Kantian concept [event]. In any case, an animal is still seeing an object as a particular object or an event as a particular event. And this is where Tye does indeed use a near-Kantian term – “categorization”. Through the Kantian categories, minds/persons individuate objects and events.

A person could have experienced a murder and not experienced it as a murder. This doesn’t mean that no concepts were applied to that event or experience. He certainly experienced it as something. A dog that experienced the murder wouldn't have experienced it as a murder. It would, however, have applied concepts to it. It would have experienced it as an individuated and therefore a determinate event. (It may have been frightened by it.)

The upshot is that (Kantian) experience needn't be propositional or linguistic; though it must be conceptual.

                                 ********************************************************

Note: the above was written in 2005/6. Hilary Putnam, for example, radically contradicts the position I adopted at that time. For example, in Putnam's paper 'What Is Innate and Why: Comments on the Debate' (1980), he writes:

“... to have a concept is to have mastered a bit of theory, that is, to have acquired the characteristic uses of such expressions as... and some key beliefs, expressed by sentences involving such expressions, or equivalent symbolism.”

However, later he writes:

“I don't claim that all concepts are abilities to use symbolism; an animal that expects the water to reach the same height when it is poured from a pot back into the glass might be said to have a minimal concept of conservation, but I claim that anything like the full concept of conservation involves the ability to use symbolism with the the complexity of language in certain ways.”

References

Church, Jennifer, 'Fallacies or Analyses?' (1995)

Kant, Immanuel, A Prolegomena to Any Future Metaphysics (1783/2004)
Peacocke, Christopher, A Study of Concepts (1992)
Tye, Michael, 'A Representational Theory of Pains and Their Phenomenal Character' (1990)

Michael Devitt on Laurence BonJour's Neo-Rationalism

i) Introduction

ii) Analyticity

iii) Our Rational Insight into the Necessary Features of Nature

iv) A Priori Logic?

The Australian philosopher Michael Devitt (1938-) makes an empiricist point about necessity in science. He accepts that scientists discovered that water is H₂O. However, scientists didn’t also discover “that [water] necessarily is H₂O”. In other words, “necessity is not an empirical discovery”. Or, in yet other words, “we do not simply observe the necessity of water being H₂O”.

Indeed what would such an observation of necessity be like even if conceivable? Where does this necessity come from? What does it add to the scientific or any picture? And, semantically, what does it mean to claim that “water is necessarily H₂O”?

All that said, not even empiricists believe that every entity of science can be observed or that science is literally all about observation. So Devitt adds:

“We do not observe most scientific facts: we discover them with the help of a lot of theory.”

So, at the very least, an empiricist may also add:

Theory helps us get at the empirical facts.

Yet not even scientific theory can help us discover the supposedly essential or necessary features of a given scientific fact, object or event. That because these modal terms are not in themselves scientific — they are philosophical and/or logical.

Analyticity

It’s an interesting to note that after discussing analyticity and its relation to the a priori, Michael Devitt says that the American philosopher Laurence BonJour (whom he classes as a “neo-rationalist”)

“has no more faith in attempted explanations [of the a priori] in terms of analyticity than I have and gives an excellent critique of their failings”.

In a sense, Devitt is right — and a philosopher like W.V.O Quine would have agreed with him. That is, in the first half of the 20th century analyticity was deemed to be the key to the a priori or at least to our understanding of it. (That’s one reason why Quine spent a lot of time on analyticity in his ‘Two Dogmas of empiricism’.) That said, it still seems that Laurence BonJour doesn’t need — or even want — analyticity to demonstrate his rationalism (or apriorism). He doesn’t care if analyticity “makes the a priori palatable to the modern mind”.

So why did analyticity become “palatable to the modern mind” in the first place?

It did so because it treated the a priori (as well as necessity) as primarily — or indeed only — a linguistic matter. Clearly it’s not only — or at all - a linguistic matter to BonJour himself. Synonymy of terms (or concepts) doesn’t matter to BonJour. What matters is what BonJour calls “rational insight”. (As it did to Edmund Husserl with his essences and meanings — see here.) And that has nothing much — or at all — to do with language, analytic statements or analyticity itself.

Our Rational Insight into the Necessary Features of Nature

So what does BonJour mean by “rational insight”?

In terms of a priori justification, rational insight

“occurs when the mind directly or intuitively sees or grasps or apprehends… a necessary fact about the nature or structure of reality”.

Necessity is not, then, a question of language, the synonymy of terms and all the rest. It’s about the nature (or structure) of reality itself.

Instead of talking about words, concepts or meanings, BonJour talks about “properties” or the “properties of the world”. Thus we must immediately ask how the mind can grasp a priori (or by rational insight) anything about the world.

Of course rationalists — from Plato to Thomas Nagel in our own time (see here) - have already told us about the (necessary) features or properties of the world. It was just the case that they didn’t need observations of the world (or experience generally) to tell us about them. (In Kant’s case, the necessary features — or properties - of the mind were the very “conditions of experience” of the world.)

But what does all this highfalutin stuff actually mean?

We all know what it means in the case of Plato, Kant and others. But what about Laurence BonJour in our own day? As Michael Devitt puts it:

“[O]ur problem of explaining the a priori becomes that of explaining rational insight.”

What does BonJour offer that Plato, Kant and the rest didn’t offer? Perhaps he doesn’t claim to offer us anything new. Or perhaps only his language (or his technical terms) are new. (This may be yet another case of Jacques Derrida’s “sign-substitutions”.)

I’ve asked all these questions about rational insight while already knowing that BonJour himself says that “we do not presently have anything close” to an explanation of it. Yet perhaps that in itself is no reason to reject rational insight out-of-hand — and it certainly isn’t a denial of its reality.

So perhaps rational insight is unanalysable or primitive in nature. And, if that’s the case, then this doesn’t — automatically — mean that it is “objectionably mysterious, perhaps even somehow occult”. Instead of being mysterious (or even occult) we can see rational insight as being “fundamental and irreducible” instead. And, if we accept that, then it may be “in no way puzzling or especially in need of further explanation” (BonJour, in Devitt).

That last phrase, however, is a little hard to swallow —i.e., something’s being in no need of further explanation. (Many such things have existed — and still exist — in both philosophy and science.) Devitt doesn’t like this. He seems to suggest that BonJour’s happy acceptance of the inexplicability of rational insight is brought about by his fear of the “intellectual suicide” which we’ll effectively (or seemingly) commit if we throw the a priori overboard — as many (or all?) naturalists have attempted to do.

Yet philosophical naturalists needn’t be so hard on BonJour.

That warning can be explained through a similar case.

Many people think that eliminativists — or “reductionists” — in the philosophy of mind reject things that are (as it were) staring them in the face — whether that’s consciousness, mind or qualia. The same is true with rational insight. We all have — or use — it. So just go ahead and carry out an example of modus ponens and then you’ll find it hard to reject BonJour and embrace Devitt’s epistemic eliminativism.

More technically, what none of us can reject is the “the intuitive or phenomenological appearances” (BonJour, in Devitt) of rational insight. There is (as Thomas Nagel put it, if about something else) “something it is like” to have rational insight. That something it is like is, perhaps, all we need to see where BonJour is coming from. Indeed these “appearances” must surely prove to be “extremely obvious and compelling” to all but the intellectually blind. Thus to deny rational insight is like denying the pain in one’s tooth.

Incidentally, just as what it is like to experience pain is hard to explain, so BonJour accepts rational insight “even if we can’t explain it”. That’s primarily because even though we can’t explain it; we can still know it. And that, to BonJour, is enough.

Having provisionally accepted BonJour on all the above, it can now be argued that it’s not the phenomenological reality of rational insight (or its what-it-is-likeness) that’s the problem: it’s BonJour’s long jump from there to “the necessary character of reality” (BonJour, in Devitt). We can accept everything about the phenomenology in the case of logical truth or modus ponens (though Devitt doesn’t seem to). However, this stuff about the necessary character of reality… that’s a jump if ever there was one.

Devitt himself says that “[n]othing in the phenomenology supports” this stuff about nature (or reality) and its necessary character. However, traditionally it was only the a priori (or rational insight) which (as it were) gave us anything necessary about nature (or reality). So BonJour isn’t claiming anything new here. Indeed he’s a soi-disant “old-fashioned rationalist” — so perhaps we shouldn’t expect anything too new from him (i.e., other than terminology).

Again, we can ask the following question:

What non-experiential link to nature (or reality) could support insights into its necessary character?

This is the clash made by the supposed link between non-experiential rational insight and… well, the empirical world.

A Priori Logic?

Despite what’s just been said, Devitt’s radical — or even eliminativist — position towards the a priori isn’t only aimed at this strange link between rational insight and the necessary features of nature/reality— it’s also aimed at the ostensible a priori nature of logic itself. Devitt concludes with what he calls a “nice abduction”. He writes:

“[O]ur knowledge of mathematics, logic, and the like cannot be explained a priori; an empirical explanation of it is the best.”

Yet just as it was argued that BonJour’s apriorism (or rationalism) is not entirely new, so Devitt’s extreme empiricism regarding the a priori in logic is not entirely new either. More clearly, Devitt’s words above could almost have been written by J.S. Mill (1806–1873) over a 150 years ago (see here). Yet despite Mill, that other great empiricist — David Hume (1711–1776) — happily accepted the a priori and necessary status of both logic and mathematics. Of course, there’s also some dispute about Hume’s precise position on logic and maths too (see here).

References

BonJour, Laurence, ‘Is There a Priori Knowledge?’ (2005)

Devitt, Michael, ‘There is no a Priori’ (2005)

[I can be found on Twitter here.]

Michael Devitt on Analyticity & Conceptual Containment

 

Michael Devitt tackles the frequently-used

“All bachelors and unmarried men.”

example as an ostensible case of a priori knowledge. This time, however, instead of talking about ‘synonyms’, ‘meanings’ or 'mutual definitions’, he talks in terms of concepts. In fact his statement of the case has a Kantian ring to it. He says that “the content of the concept [bachelor] ‘includes’ that of the concept [unmarried]”. Kant, though, talked of conceptual ‘containment’ rather than inclusion. And, as Quine told us about the Kantian metaphor ‘contained’, the word ‘includes’ is also difficult.

How does one concept ([bachelor]) contain or include another ([unmarried])?Anyway, because these concepts are seen this way, the above is taken to be an analytic statement or taken as being known to be true a priori.

Devitt puts his own slant on this well-known example of an analytic statement. He claims that others believed that

“simply in virtue of having a concept, a person was in possession of a 'tacit theory' about the concept; in virtue of having [bachelor], a person tacitly knew that its content included that of [unmarried]”.

We can say that if a person were asked for a definition of the word ‘bachelor’, he would say that “a bachelor is an unmarried man”. However, because his theory is tacit, he doesn't vocalise (or even sub-vocalise) that definition every time he uses the word ‘bachelor’ – perhaps he's never done so. Though when asked, he could indeed do so. We can assume that simply having heard - and then known - the definition, then that's enough for such tacit knowledge. Of course because it's tacit, he almost certainly wouldn’t talk about “conceptual containment” or one concept being contained within another. Perhaps his only technical knowledge would be definitional.

The former a priori explication of these concepts and the a priori statement above are seen as Cartesian by Devitt. We have a “privileged 'Cartesian' access to the facts about [such] concepts”. Presumably this must mean that we need no experience of concept-use and we certainly don’t need to check a dictionary. The only thing that's required is

“a reflective process of inspecting the contents of concepts to yield knowledge of the relations between them which in turn yield such knowledge as that all bachelors are unmarried”.

This is odd to those of us who see concepts as themselves (often) being the contents of statements or mental states. Concepts are often seen as being pretty primitive and therefore suitable candidates for the contents of various things. On this picture, concepts themselves have content. Thus:

The content of the concept [bachelor] is the concept [unmarried man].

Does that mean that a concept, qua content, contains another concept? Thus we would have:

[ bachelor [unmarried man]] or [unmarried man [bachelor]]

All this also went under the name of “conceptual analysis” and was similarly seen as an a priori process. Indeed at one point, because of the importance of conceptual analysis in philosophy (at least at one time), it was often stressed that philosophy itself was an essentially a priori business. Either that, or it was a way of stressing the already-taken-for-granted view that philosophy is an a priori business. (Some philosophers still believe that conceptual analysis is the primary role of a philosopher. Thus that philosophers are basically apriorists.)

Devitt also brings in the epistemic notion of justification. This seems a little out of place, prima facie, when it comes to the statement “All bachelors are unmarried men”. However, we're talking about a priori justification here. He asks us if we can justify the “proposition that all unmarrieds are unmarried were justified” (6). Well, of course it is – isn’t it? What we have here is the Quinian reduction of the analytic truth

“All bachelors are unmarried men.”

into the logical truth

“All unmarried men are unmarried.”

by the “substitution of synonym for synonym”. Again it seems, prima facie, like an odd question to ask “where does the justification for this proposition come from?” (6). Of course it's justified… Well, if it isn’t exactly justified, that’s because it doesn’t need to be because it's a logical truth. However, the apriorist has previously said that the statement “All bachelors are unmarried men” is known to be true a priori and therefore it's also justified a priori. Now it seems it doesn’t require epistemic justification because it's a disguised logical truth.

The obvious question now follows (asked earlier in Devitt’s paper): What justifies logical truths? This question wasn’t asked much until fairly recently in either philosophy or logic. Though if the analytic truth is a disguised logical truth (even though it was classed as a priori justified), then “we have not described a nonempirical way of knowing” (6) precisely because the apriorist has shifted (if he has shifted) from an analytic statement justified to be true a priori to a logical truth which hasn't received such a justification.

A question Devitt doesn't ask here is: Can logical truths be justified?

Reference

Devitt, Michael, 'There is no a Priori' (2005)

 

Is Ontic Structural Realism Merely a Philosophy of Quantum Mechanics?

This piece is a short introduction to the close relation that can be found between ontic structural realism and quantum mechanics. A more detailed commentary on the 'Ontic Structural Realism and the Philosophy of Physics' section of Everything Must Go (by James Ladyman and Don Ross) will follow shortly.

Introduction

“Current physical mathematics, especially models of quantum entanglement, are thus crucial to motivating OSR.” - Don Ross ( 'Ontic Structural Realism and Economics'

It's very clear to me that almost the entire ontic structural realism (OSR) project is motivated by findings and theories in quantum mechanics (QM). In other words, findings in the micro-world; not in the macro-world. One can immediately conclude from this that OSR certainly has very little to do with “medium-sized dry goods” (as J.L. Austin once put it) – at least as an inspiration.

In that respect, one can happily agree with the ontic structural realists (OSRs) when they say that QM isn't about “entities or objects”. The thing is, I don't really think that many philosophers (or even all educated people) ever did see protons, electrons or even atoms as objects or entities in the everyday sense.

So when a OSR says:

If you want to insist that a electron is an entity of some kind, then please show me something beyond the data and mathematical structure.

We can reply to that by saying:

But who, exactly, would disagree with the "data and maths" bit of your statement? And how strong and detailed do you think the layperson's - and even philosopher's - commitment to thinghood in the quantum domain is?

Indeed how could a layperson offer us more on an electron than a physicist or a philosopher of science? Nonetheless, it's still data about something and maths about something. Otherwise it's pure maths and there would be no real need for the word 'electron' or even for electrons themselves.

In other words, why do all (or most?) OSRs think that the people who disagree with them only have a commitment to medium-sized dry goods in every domain? That is, a commitment to only those objects they can kick?

When Dr Johnson showed Bishop Berkeley that he could kick a rock: the Bishop was unimpressed. I'm not impressed either. And most philosophers aren't.

When the OSR says that science (or physics) doesn't give us objects, we can say that this was something Berkeley has already said. It was something the British Empiricists and various kinds of idealist said. And, indeed, something many scientists have said; at least since the late 19th century.

Isn't it also the case that sections (if small ones) of the educated West have known that the billiard-ball/solar-system model of the atom is a model since, say, the 1930s? They also know that they can't kick atoms. They know that, in a sense, atoms and definitely protons aren't everyday objects or even objects at all. They also know that models are... well, models.

In any case, even more specifically than quantum mechanics (generally) being a prime motivating force for OSR, quantum entanglement specifically seems to loom large in the literature.

Clearly it's the nature of quantum phenomena which are seen as undermining “traditional metaphysics” by OSRs.

Finally, we can object to OSR without having an explicit commitment to the existence of objects/entities in every domain (specifically in QM!). We simply need to say that that there's more than numbers, equations or "structure" in physics generally and even, specifically, in quantum physics.

In the end, then, all this will depend on what the protagonists in this debate take objects to be. After all, the nature of objects (as well as their very existence) has been discussed in metaphysics for over two thousand years.

Individuals in Quantum Mechanics

As said earlier, OSRs get their point across by bringing QM into the debate.

What are said to be “individuals” or objects (though by whom?) are such things as quantum particles and other spacetime points. According to OSR, the reason why they aren't in fact individuals is logical in nature. In that sense, we're talking about the logic of quantum mechanics here.

For any thing (x) in quantum mechanics, we can say that the law of identity doesn't hold for that x. (In symbols: ∀x (x = x).) That is, x isn't identical to x .(In symbols: x ≠ x or ¬(x = x).) Now why is that?

However, it's acceptable to quantify over what OSRs call “non-individual objects”. That is, such an x can be the value of a first-order variable. Despite that, usually objects (even if non-individual) are seen to be the subject of the law of identity. Though perhaps that's only the case if they're - or if they're seen as – substances with intrinsic properties.

How does this claim fit in here? Is it that because some relations are seen as being ontologically on a par with individuals that the latter are seen not to exist? However, claiming that relations are ontologically on a par with individuals isn't the same as claiming that individuals don't exist.

Quantum Entanglement

The main point about quantum entanglement isn't that relations somehow constitute particles: it's that physicists attribute exactly the same intrinsic and relational properties to each (pair) of particles. Thus, at a prima facie level, it can be said that it's not really a surprise if OSRs deem relations to be everything.

This is how Ladyman and Ross put their position:

“... quantum particles appear sometimes to possess all the same intrinsic and extrinsic properties. If two electrons really are two distinct individuals, and it is true that they share all the same properties, then it seems that there must be some principle of individuation that transcends everything that can be expressed by the formalism in virtue of which they are individuals.” (page 148)

This means that everything that's true of a must also be true of b simply because a and b are entangled. (In symbols: (x) (y) (F) (x = y ⊃. F (x) ≡ F (y).) Such entanglement effectively means that a and b can't been disentangled or taken as two objects.

To put more meat on this bone of quantum entanglement, it can be said that if we take two fermions (such as electrons), the spin of a (in any given direction) is the “opposite” of the spin of b. a has spin in relation to b and b has spin in relation to a. Indeed a and b simply don't have spin when taken on their own. It's also said that a and b are given the same spatial wave-function when they're both in the first orbit of an atom.

Again, it's as if a and b are one. Or, at the very least, they can't be taken independently. Of course it can now be said that if a and b can never be taken independently, then in what sense are they individuals? Perhaps it can either be said that a and b are as one (i.e., they constitute one object) or that they aren't individuals/objects in the first place. That is, every individuation of a will include an individuation of b. Or, alternatively, it can be said that there can be no independent individuation of either a or b.

Opposite Spin

Ladyman and Ross argue that relations are fundamental when it comes to fermions. They believe that fermions don't have intrinsic properties – they only have relational properties. (This is also called “contextual individuality” in the literature and can also applied to all spacetime points, not just to fermions.)

Having opposite spin is clearly a relational predicate because of the word “opposite” - opposite to what?

In this case it's fermions which have opposite spin when they're in what's called the “singlet state”.

However, a problem for OSR can immediately be spotted here.

The relational property [opposite spin] can be summed up in Leibnizian logic by the term “irreflexive relation”, which is symbolised aRb (with the R symbolising “opposite spin”). However, what about a and b – the relata – themselves! Surely a and b (electrons, for example) have to be seen as individuals of some kind.

It's certainly true that when it comes to both a and b having the property opposite spin, then clearly that property is relational – indeed fundamentally relational. Thus the property is relational and (it can be argued) it's also more important than both a and b. It's certainly more important (or fundamental) than any seemingly intrinsic properties (which are rejected, by definition, by OSRs).

Again, are relational properties fundamental? This is an important question because some metaphysicians haven't seen relational properties as bona fide properties at all. Such metaphysicians don't believe that relational properties are genuine properties of objects or entities. OSRs, on the other hand, are going in the opposite direction to this.

Another question that can be asked here is:

Can relational properties individuate individuals/particles/things?

What we have here is a chicken-or-egg situation.

On the one hand it can be argued that it is individuals (or a and b) that give individuality to the relations. On the other hand it can be said that relations give individuality to individuals.

Is that a difference that makes a difference?

Perhaps the individuality of a and b is the sum of both intrinsic and relational properties. In any case, a and b are bound to have some relational properties; whether that's opposite spin or bigger/smaller than x.

On the other hand it can be argued that an individual wouldn't have the relational properties it has without also having what can be called intrinsic - or even essential - properties. At the very least, individuals must have properties which are over and above their relational properties in order to have those relational properties in the first place!

... and finally intuitions...

There's a lot of intuition-talk from Ladyman, Ross and other OSRs.

Are they referring to our intuitions about the causes of World War Two or the existence of aliens? Not really; when you scratch the surface, it seems that OSRs are talking about our intuitions regarding quantum phenomena.

Take leptons.

I have zero intuitions about leptons. I would suggest that no one really has intuitions about leptons. Perhaps people have intuitions about God, cats and thermostats; but leptons? Surely not.

I've also heard talk about our intuitions regarding such things as “intrinsic donkeyhood” (chose your own xhood).

Who on earth has intuitions about a deeply metaphysical notion such as intrinsic donkeyness, let alone about intrinsic atomness or electronness? It's a metaphysical technical term or notion. Therefore what has intrinsic donkeyhood got to do with intuitions?