Reconsidering the Place of Dualism in Medicine and Psychiatry – A Dialogue with Diane O’Leary

This interview is part of a series featuring in-depth conversations intended to foster a re-examination of philosophical and scientific debates in the psy-sciences. It is a continuation of my prior series, “Conversations in Critical Psychiatry,” but with a broader focus and a new orientation.

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Diane O’Leary, PhD is a philosopher, a disabled independent scholar whose work is centered on the overlap between philosophy of medicine/psychiatry and philosophy of mind. She’s been a visiting faculty member at the Center for Philosophy of Science at University of Pittsburgh and the Rotman Institute of Philosophy in Ontario. O’Leary has published key articles and chapters on dualism, consciousness, and medically unexplained symptoms, along with public writing and interviews in Stat News, IAI News, Vice News and elsewhere. She’s a frequent speaker, and a member of the Primary Care Research in Diagnostic Error Learning Network at Brigham and Women’s Center for Patient Safety. Currently she’s toggling between two books-in-progress, one for general readers, Gaslight: How Bad Philosophy Corrupts Good Medicine, and the other for clinicians and academics, Medicine’s Mind-Body Problem: A Safe, Sound Solution. You can find her on twitter @DianeOLeary.

Awais Aftab, MD is a psychiatrist with philosophical interests.

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Aftab: Your impressive work on dualism in medicine and psychiatry has forced me and many others in medicine and psychology to reexamine long-standing assumptions. I’d refer readers to your papers on medicine’s metaphysical confusion (Synthese, 2021), the biopsychosocial model (EuJAP, 2021), and your recorded talk as part of the philosopher of psychiatry webinar series to learn about your views in detail. Can you, however, briefly explain your argument that medicine has misunderstood dualism?

O’Leary: Many thanks for the kind words, Awais. The misunderstanding has its roots in George Engel’s work. Along with a whole lot of rich and valuable insights, Engel offered two confused philosophical claims. First, dualism and reductionism combine in the biomedical model, and that’s the source of its problems. Engel attributed the combination to Descartes, and he offered the biopsychosocial model as a remedy for both. Second, dualism is the separation of mind and body in our thinking, language, or medical practice. To fix the biomedical model, then, all we need to do is to change the way we think, talk, and practice in relation to mind and body. If we stop separating them, if we just orient ourselves around the person holistically, dualism and reductionism will go away, and all will be well. 

The thing is that it’s actually impossible for the biomedical model to embrace reductive dualism, or dualistic reductionism, because that’s like saying that it’s both day and night, that the lights are both on and off, or your new dress is both beautiful and hideous. Dualism and reductionism about mind and body are diametrically opposed views that cannot both be true. More importantly, dualism is not the separation of mind and body in our thinking or practice.  In fact, dualism is not something we do at all. Descartes is not a dualist because he thinks of mind and body as separate. He’s a dualist because he thinks both minds and bodies exist, and they’re going to keep on existing as two things no matter what anybody says or does. 

Why does this matter for medicine? It matters because Engel was right that medicine’s view on mind and body has a big impact on its success at helping people be well. First, the campaign to stop thinking of mind and body as separate is self-refuting if we accept Engel’s goals, and no science is at its best when its foundations are faulty. When we succeed in seeing mind and body as one, we are reductionists—but reductionism is the problem that Engel sets out to address. Second, well-meaning people in medicine, psychiatry, psychology, and bioethics believe they must try to eliminate the separation of mind and body in their thinking and language because philosophy says that’s a good idea. But philosophy says no such thing. As far as philosophers are concerned, if some form of dualism is true, it’s going to keep on being true even if no one ever thinks or speaks of it again, ever.

Finally, effort to avoid “dualism” interferes with patient care. (I put “dualism” in quotes when I’m referring to separation of mind and body.) In cases of unexplained symptoms, for example, clinicians are advised to end diagnostic effort because it’s “dualistic.” It’s hard to imagine any action more basic to medicine than effort to find disease that needs treatment, but for the many cases where diagnosis remains unclear, medical training prioritizes avoidance of separation of mind and body. Similarly, in countries where aid-in-dying is permitted for mental illness, avoidance of “dualism” has been the primary supporting argument. What’s permitted for medical illness, the argument goes, cannot be denied for mental illness, because to do so would be to separate mind and body. Regardless of what we might think about that practice, it sure seems clear that lives should not be ended on the basis of a misguided definition of dualism. Even the DSM has apologized for implying that mind and body are separate, confessing that, despite effort, “dualism” has yet to be overcome.

I recognize that it’s very difficult for people in medicine to imagine that dualism is not what they think it is, and that philosophy doesn’t care about controlling how we think and talk about it—but bad philosophy is not benign in medicine. This is something we need to address.

Aftab: One thing I want to note is that philosophers themselves are deeply divided on issues related to dualism and philosophy of mind. For instance, in the 2020 PhilPapers survey of philosophers, 52% accepted (or leaned towards) physicalism, while 32% accepted non-physicalism (N=1733). On the issue of consciousness, 22% accepted dualism, 4.5% accepted eliminativism, 33% functionalism, 13% identity theory, and 7.5% panpsychism (N=1020). I hesitate to ask psychiatrists to take a strong position on a matter that commands no consensus among philosophers. 

O’Leary: Let’s think through the idea that there’s no consensus among philosophers on the issue of dualism, because that’s not an accurate conclusion about this survey. On the choice between physicalism and non-physicalism, folks in medicine will assume that this question is really a choice between physicalism and dualism. Philosophers won’t see it that way, though, because philosophers aren’t thinking of Descartes when they see ‘dualism.’ They’re thinking of a new form called ‘property dualism.’

Susan Schneider explained this beautifully, “contemporary philosophy of mind sees the question of the nature of substance as being settled in favor of the physicalist. Dualism about properties, in contrast, is regarded as being a live option.” So we’ve settled the question of Descartes’ dualism against Descartes. We agree now that all things are physical things, even human beings. But that doesn’t settle the question of dualism because we still need to ask: how many of us physicalists are dualists about properties? That’s a live question in our time, so the fact that most philosophers are physicalists tells us nothing at all about the popularity of dualism.

The same kind of problem arises with the question of consciousness. Folks in medicine assume that all the “isms” on this daunting list—dualism, eliminativism, functionalism, identity theory, panpsychism—are mutually exclusive, so if you accept one, you reject the others. That’s a misunderstanding. Many forms of functionalism are forms of property dualism (e.g. Shoemaker), because, as the Stanford Encyclopedia of Philosophy puts it, functionalism is “officially neutral” on dualism. It’s hard to say what proportion of functionalists are property dualists, but this poll certainly doesn’t tell us that only 22% of philosophers are open to dualism. In fact, many panpsychists are property dualists too.

The clearest line we can draw within the list of “isms” is not between dualism and the rest, but between views compatible with dualism and those diametrically opposed to it. On the yes or maybe side you’ve got dualism, panpsychism and functionalism, and together that’s 63% of philosophers—three times more than you get on the absolutely no side, with eliminitivism and identity theory. If you’d taken this poll in, say, 1970, the imbalance would have leaned just as far in the opposite direction, so things have dramatically shifted. 

There are two lessons for psychiatry to draw from philosophers’ perspective on the mind-body options. First, dualism is not the separation of mind and body in our thinking and language. That idea does not appear on the survey. Second, dualism is not about Descartes. It’s about property dualism, and that’s a big broad umbrella idea that can accommodate a wide range of positions. Emergence, supervenience, panpsychism, naturalistic dualism, even functionalism—all of these views are either defined in terms of property dualism or potentially open to the idea. Fifty years ago philosophy fiercely opposed dualism, but that’s no longer the consensus.

O’Leary: There are two lessons for psychiatry to draw from philosophers’ perspective on the mind-body options. First, dualism is not the separation of mind and body in our thinking and language. Second, dualism is not about Descartes. It’s about property dualism, and that’s a big broad umbrella idea that can accommodate a wide range of positions. Emergence, supervenience, panpsychism, naturalistic dualism, even functionalism—all of these views are either defined in terms of property dualism or potentially open to the idea.

Aftab: A related aspect of the hesitation I mentioned earlier is that it's evident that psychiatry accepts the ordinary existence of subjective experience and mental states, but it's not clear to me that psychiatry has to take any particularly strong position on whether these mental states are, in some fundamental ontological sense, radically different kinds of things than physical states of the brain. (I’m borrowing the language here from Stanford Encyclopedia of Philosophy: “In the philosophy of mind, dualism is the theory that the mental and the physical – or mind and body or mind and brain – are, in some sense, radically different kinds of things.”)

O’Leary: For the first part of your hesitation, then, dualism actually does command consensus among philosophers—at least insofar as true reductionists, eliminitivists, or identity theorists have now become rare. Regarding this second part, where you hesitate to ask psychiatrists to take a position on which mind-body option is right, the main point I’d like to make there is, well, me too. I don’t generally shy away from strong views, but on the issue of which “ism” is the right one for medicine or psychiatry, I’ve never made any claims. What I’ve said is that medicine and psychiatry are confused about what the word ‘dualism’ actually means in philosophy, and when we correct that, we find that medicine is already based on property dualism, particularly psychiatry.

O’Leary: on the issue of which “ism” is the right one for medicine or psychiatry, I’ve never made any claims. What I’ve said is that medicine and psychiatry are confused about what the word ‘dualism’ actually means in philosophy, and when we correct that, we find that medicine is already based on property dualism, particularly psychiatry.

You’ve said, “It's evident that psychiatry accepts the ordinary existence of subjective experience,” and I think you’re right about that. In fact, I can’t imagine anybody disputing it. The thing is that this is an assertion of property dualism, plain and simple. You’re saying that psychiatry accepts that subjective experiences exist, and that’s an ontological claim no matter how you slice it. You’re not saying that experiences are things, of course, in the sense of substances. You’re saying that experiences are states, or properties, that human beings have.

The reality of experience is so obvious to people in mental health fields that it seems like it can’t possibly be a substantive claim. But in the context of philosophy it is. In fact, the existence of experience is precisely what we’re debating with the question of dualism. When you accept that there are properties of experience, you actively distinguish those from physical properties of the brain. You recognize that the way you feel when you’re tired and you get hold of your morning coffee is distinct from the biochemical facts that characterize the state of your brain at that moment. No matter how committed we are to catch-phrases like “integration of mind and body,” your first taste of morning coffee is a private fact, a subjective fact, while the physical state of your brain at that moment is a public fact, an objective fact. I know we both agree that these are correlated in some deep and inextricable way, but they’re distinct just the same. In fact, they couldn’t be correlated if they were not distinct.

Aftab: When we talk about the mind, it seems we can easily fall prey to a conflation of mind as referring to consciousness (subjective experience, qualia, phenomenology, etc.) vs mind as referring to the cognitive, behavioral, or psychodynamic aspects that show up in psychological theorizing, e.g., memory, learning, executive functioning, perception, motivations, defense mechanisms, etc. Many neuroscientists would say that cognitive “information processing” in the cortex can take place, and routinely takes place, without conscious awareness. Solms writes, for example: “It is well-established that learning and memory can exert their effects without any “inner feel”; and the same applies to perception. Hence the title of (Kihlstrom's, 1996) celebrated review article: “Perception without Awareness of What Is Perceived, Learning Without Awareness of What Is Learned.”” (Solms, 2019)

In other words, there is more to mind than consciousness. This seems important to me because a lot of the philosophical debate around dualism centers on consciousness, while psychology and psychiatry are usually interested in many other psychological aspects as well. Does it make sense to be a “dualist” about processes such as memory and learning?

O’Leary: Maybe there’s a simple way to characterize what you’re suggesting and a more complicated way. The simple way is probably just the difference between access consciousness and phenomenal consciousness, and that’s largely what Solms is getting at. Phenomenal consciousness is usually what we mean by “consciousness,” that is, qualitative, first-person, subjective experience. Philosophers often see a difference between that and the aspects of mental activity, like learning or executive functioning, that go on without first-person experience. This helps us isolate the question of dualism as a uniquely “hard” problem. We can use neuroscience and cognitive science to explain cognitive activities of the brain. But there’s good reason to think that facts about the brain (at least as we currently understand them) cannot explain why any particular brain activity should also be accompanied by the private, “what it’s like” feel of first-person experience. If you’re someone who thinks this challenge is indeed uniquely difficult, then you’re open to dualism in some way. 

I think you might be getting at something deeper though, too, and it seems closely related to something I’m working on with Marie Nicolini. I think you’re suggesting that each of us is more than a “stream of consciousness,” so there’s a lot going on within a mind that’s sub-conscious or un-conscious rather than non-conscious. I take this distinction to be meaningful and important. My mind is engaged at this moment with my experience of the temperature in this room and the vague sense of hunger in my stomach, but these would not have entered my stream of consciousness if I hadn’t gone looking for some things I experience that I’m not aware of. So these are facts about my mind that I can discover if I go looking for them, but I do have to go and explore. Similarly, my mood suggests that somewhere “beneath the surface” I’m engaged with feelings about my son, or concern about my father’s health. I could bring these experiences into my stream of consciousness if I set out to do that—say, in therapy—but if I don’t, they remain so far out in my periphery that if you asked me what I was thinking about, I wouldn’t mention them.

The access/phenomenal distinction has really not captured this kind of thing. In fact, philosophers have not had much to say about our ability to investigate the depth and complexity of our current experience as we do in psychiatry. This is honestly part of the motivation for the work I do. As I’ve said, I think psychiatry will do a better job of supporting and protecting mental health if its mind-body picture is philosophically coherent—but the other direction is at least equally important to me. I’m certain that philosophy would do a better job of making sense of the mind if it engaged with psychiatry. Right now that’s not possible, because psychiatry can’t speak philosophy’s language.

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Aftab: How much can we infer about the nature of mental disorders from a metaphysical position on the mind-body relationship? I’m doubtful that a metaphysical view such as property dualism, by itself, supports or challenges any particular view on the etiology of psychiatric disorders or says much about the appropriateness of diagnosis, pharmacological treatment, or the medical framework in psychiatry. Whether the medical model applies well or poorly to psychiatry seems to be an issue that is orthogonal to property dualism. What do you think?

O’Leary: That’s a great question. First, if we want to make sense of the nature of mental disorders, we’ll need a coherent picture of what “mental” means. I haven’t offered that—I mean, as I’ve said, there’s nothing prescriptive about my suggestions for psychiatry, except to get its philosophical house in order. Psychiatry is in a real stew at the moment, with every kind of foundational question up for grabs. I think this kind of breaking point was inevitable because the mind-body picture that underlies psychiatry has been incoherent for a long time. How can the field respond to a complex challenge like the antidepressant debate if we don’t even know what we mean by “mental,” and we have no coherent options for making sense of the relation between mental and physical? How can it begin to respond to discoveries about consciousness, or the idea that mental illness might be social?

O’Leary: There’s nothing prescriptive about my suggestions for psychiatry, except to get its philosophical house in order. Psychiatry is in a real stew at the moment, with every kind of foundational question up for grabs. I think this kind of breaking point was inevitable because the mind-body picture that underlies psychiatry has been incoherent for a long time.

This much about dualism is certain to be useful in any discussion on the nature of mental disorders: go ahead and separate mind and body! It will not be possible to make sense of mental disorders—as distinct or not distinct from purely biological diseases—unless we can freely consider the difference between the subjective experiences of the human being in front of us and the biochemical states of her brain. Mental disorders begin with the mental.

Second, once we recognize that psychiatry assumes property dualism, we open the door to an account of mental disorders that’s grounded in subjective experience. I’m not saying that’s the only right view (though it is a view I’m working out). At this point I’m just saying that this is a debate that must be had. Psychiatry needs to consider what a disorder of experience would amount to, and how it would be different from, but related to, purely biological disease. That’s going to require new philosophical clarity.                                                                                      

We’re starting to see a lot of new effort in this direction from phenomenology and from consciousness studies reaching over into psychiatry. There’s a marvelous paper called, “Putting the “mental” back in “mental disorders””, by Traschereau-Dumouchel and colleagues last year, and there’s “Taking subjectivity seriously”, by Kyzar and Denfield, which ties new insights from phenomenology and psychiatry to neuroscience. Then there’s Cecily Whiteley’s marvelous paper, “Depression as a disorder of consciousness”. This new kind of inquiry is deeply opposed to the campaign against dualism, so a new conceptual foundation is going to be important.

Aftab: You've persuasively argued that medicine and psychiatry have gotten dualism wrong, that they have misunderstood a metaphysical position about the existence of minds with the doctrine that the mind is separate from or disconnected from the body. You are right about the error. But it does nonetheless seem that the tendency to disconnect the mind from the brain is a tendency that needs to be guarded against in medicine and has historically been a problem in its own right (even if dualism is not the right term for it).

O’Leary:  Well, thanks for saying so about the error. There are good reasons for thinking that a sense of wholeness is important not only to our well-being, but to our physical and mental health. But it’s important to think critically about what we’re actually saying with that idea. We’re not saying that there’s no difference between an experience and a bodily state. If that was our view, we’d be reductionists, so holism would be impossible. We’re saying that although we recognize the difference between our experiences and the brain activities they’re correlated with, we’ll lead better lives if we avoid the trap of imagining that we’re two divided things, mind and body, that are oddly stuck together. We are embodied experiencers, that’s how I tend to think of it, and as a matter of quality of life, and health—rather than a matter of metaphysics—our lives are better when we keep that in mind.

What we’re aiming for with this kind of thing is really humanism in medicine and mental health care, and I think that’s profoundly important. Based on Engel’s philosophical mistakes, though, people have the strange idea that humanism demands rejection of dualism. That’s the opposite of how philosophers see things, and truly it’s a bizarre view. We can’t be humanists if we think that humans really don’t have subjective experience, that experience is just physical brain activity, that you and I have no more inner life than the chairs we’re sitting on. When we reject every form of dualism or panpsychism, that’s what we’re left with. 

Aftab: You’ve talked about how confusion around dualism has led to an attitude of deliberate diagnostic vagueness that has negatively impacted the care of “medically unexplained symptoms.” Can you say more about that?

O’Leary: I suggested in 2018 that “deliberate diagnostic vagueness” is what you get when you’re so serious about the campaign against separation of mind and body that you directly discourage it in diagnosis. Standards of care for medically unexplained symptoms come from research in psychiatry, and all of this research is driven by the idea that it’s bad for clinicians to separate symptoms caused by disease from those caused by psychosocial distress. To avoid “dualism,” they should accept unexplained symptoms as diagnostically vague, as mind-body problems rather than one or the other, ending the quest to determine whether disease is present. 

Clearly this approach is unsafe, because a great many people suffer from diseases that are hard to diagnose. And though it’s commonly believed that error is rare in this area, research supporting that idea is poorly designed and generally not reviewed in medicine. This isn’t rocket science. No diagnosis is going to be reliable if it’s based on philosophy rather than science, and things will go particularly badly when the philosophy is misguided. If actual philosophy of mind were driving this research instead, the challenge of MUS would be forced out of psychiatry and back into medical science where it belongs.

It's unclear to me why this issue plays such a small role in critical psychiatry discourse. Public anger toward psychiatry about this problem is substantial, and growing rapidly as Long COVID grows more common. More broadly, because medical training on psychosomatic conditions comes from psychiatry, and psychiatry continues to center on gender in diagnostic recommendations, it’s psychiatry, more than medicine, that needs to address gaslighting as a threat to women’s health. The DSM construct of somatic symptom disorder is generally understood to occur in females ten times more often than males. And while that extraordinarily dangerous figure appears regularly in reviews and practice recommendations, no one seems to think that it requires evidence. Incredibly, Medscape and American Family Physician have recommended the 10:1 ratio for years, citing only each other.

Figures on women’s difficulty accessing healthcare for serious everyday disease are uncontroversial now, and they’re nothing short of alarming. Still, we have yet to see even the tiniest bit of movement from psychiatry toward protecting women from mistaken attribution of disease to the mind. Confusion about dualism seeps into every area of psychiatry. For me, as a matter of social justice, this one is the most urgent.

Aftab: There is a problematic attitude of diagnostic vagueness for sure, but its relationship to “dualism” is complicated. We can talk about bodily (physiological) dysfunctions and mental (psychological) dysfunctions, but both sorts of dysfunctions exist across the mind-body divide. Bodily dysfunctions often present with psychological symptoms and psychological factors often play important roles as risk factors or as moderators for recovery. Psychological dysfunctions are embodied, they involve brain processes, often present with bodily complaints, and physiological factors often play important roles as risk factors. Furthermore, we can have problems that arise from a complex set of interacting physiological factors, a complex set of interacting psychological factors, or a complex set of both physiological and psychological factors. Sure, we may separate mental properties and physical properties, but there is no way to extend this sort of separation to clinical problems in a clean or straightforward manner.

Aftab: Psychological dysfunctions are embodied, they involve brain processes, often present with bodily complaints, and physiological factors often play important roles as risk factors. Furthermore, we can have problems that arise from a complex set of interacting physiological factors, a complex set of interacting psychological factors, or a complex set of both physiological and psychological factors. Sure, we may separate mental properties and physical properties, but there is no way to extend this sort of separation to clinical problems in a clean or straightforward manner. 

It is the case that in psychiatry, we have generally not found the project of separating “symptoms caused by disease from those caused by psychosocial distress” to be very productive. Paradigmatic psychiatric disorders such as depression and schizophrenia are not explainable with reference to psychosocial distress or psychosocial causation; they have causal risk factors that are distributed across multiple levels of explanation and involve psychological as well as neurophysiological mechanisms. It is also the case that meaningful (but overlapping) distinctions are to be made between psychiatric disorders and other medical disorders such as autoimmune disorders. It would be a serious error to misdiagnose an autoimmune disorder as a primary psychiatric disorders (e.g., schizophrenia), just as it would be a serious error to misdiagnose an autoimmune disorder as a primary disorder of joints (e.g., osteoarthritis) or as a primary disorder of the cardiovascular system (e.g., essential hypertension).

The problem in the case of “medically unexplained symptoms” is that clinicians end up offering bad explanations of psychosocial causes (“it’s stress”) or they misdiagnose the problem as a psychiatric disorder (as depressive disorder or as anxiety disorder, which may very well be comorbid but are not the correct diagnosis for the complaint). And this basically conveys the implicit message that the problem is “all in one’s head” and becomes a powerful form of dismissal, invalidation, and neglect.

This is all compounded by the inability of current healthcare professionals and systems to patiently work with unexplained symptoms and provide adequate care. Brian Teare has written about the experience of remaining undiagnosed after a series of medical tests: “I was betrayed by my own GP. She didn’t say the phrase It’s all in your head, but she might as well have...  I keep imagining what it would have meant to have encountered a doctor who said, I’m at the end of the care I can give you, and though I couldn’t diagnose your illness, I believe you are ill and you need more comprehensive testing than public health can provide.”

Resultantly, I can’t help but be dissatisfied with the idea that the solution to our current poor care of medically unexplained symptom lies in doubling down on some sort of dualism between “mind problems” and “body problems” when many complex, multifactorial problems cannot be neatly categorized in this manner. The essential thing, in my opinion, is a transparent acknowledgement of our ignorance and our state of knowledge, avoiding premature closure of the search for causes, resisting bad causal explanations, challenging misdiagnosis, and confronting clinical invalidation and medical neglect.

O’Leary:  I confess I’m confused by these suggestions, Awais. We’ve agreed that separation of mind and body is not dualism, and that there’s no reason to resist property dualism, but here you are suggesting that, because it “doubles down on dualism”, doctors should not try to determine whether unexplained symptoms are caused by mind problems or body problems. We’ve all doubled down on dualism, I’m afraid, because psychiatry doesn’t work unless we accept the reality of subjective experience. Philosophy provides no reason to resist dualism in diagnosis, and no reason to avoid separating mind problems from body problems. In fact, medicine gives us no reason to avoid it, because concern about separation has been (wrongly) attributed to philosophy for so long that no one has bothered to support it on clinical grounds.

You suggest that separation is unproductive in psychiatry, but I think, first, that you really don’t believe that. You recognize the difference between bodily pain and psychosocial distress, and you understand what’s happening when a patient with bodily symptoms is referred to psychiatry. If you didn’t separate mind and body in these basic ways you couldn’t function as a psychiatrist. I think what you mean to say is that psychiatry is more effective when we accept complex interactions between mind problems and body problems—and I fully agree with that. I’m just pointing out that there are no interactions at all between a thing and itself. When we provide care that recognizes mind-body interactions, we begin by separating. In this way, it’s incoherent to prohibit separation of mind problems from body problems.

O’Leary: If you didn’t separate mind and body in these basic ways you couldn’t function as a psychiatrist. I think what you mean to say is that psychiatry is more effective when we accept complex interactions between mind problems and body problems—and I fully agree with that.

Second, it’s important to think about what psychiatry communicates to a doctor-in-training when it tells her that MUS are “complex, multifactorial problems that cannot be neatly categorized.” It tells her that deliberate diagnostic vagueness is the best approach, that her usual determination to diagnose disease should be abandoned with this patient group. Most impactfully, whatever we tell doctors-to-be about unexplained symptoms, we tell them about healthcare for women—because whether we use the term MUS or somatic symptom disorder or somatization, psychiatry has trained every physician to believe that these are the most common symptoms in medicine, and they affect women almost exclusively.

If you and I see our primary care doctors today for new symptoms, I will be ten times more likely to leave the office with talk about “complex, multifactorial problems that cannot be neatly categorized”. You will be ten times more likely to leave with a diagnosis, or an uncertainty that’s understood to require resolution. If we both have pain, you’ll be more likely to get pain medication and I’ll be more likely to get sedatives. If we both have bladder or kidney cancer, with symptoms, I’ll be two or three times more likely to have to have to visit three or more doctors before one of them takes me seriously enough to refer for testing. And if we were both over 55 with heart disease, I’d be twice as likely to be misdiagnosed with a mental health condition, and seven times more likely to be mistakenly sent home from the ED in the midst of a heart attack.

When we allow pseudo-philosophy to override diagnostic caution, people die. And when we combine that approach with entrenched professional gender bias, women die. Purely as a matter of numbers, few problems in psychiatry cause harm to more people than this quiet combination. I can’t imagine any way for psychiatry to justify its lack of effort to protect women from this error.

Aftab: Ok, so I want to press you here on what exactly it is that we are trying to distinguish. We begin with property dualism, according to which there is such a thing as subjective experience. Fine. But then you go further and seem to say that accepting this property dualism also means accepting that there is a (sharp? mutually exclusive?) delineation to be made between “mind problems” and “body problems.” That, to me, is a very different sort of distinction than property dualism. Let’s take a patient of chronic pain who has lumbar radiculopathy. There is the subjective experience of pain, and there is the activity in the nervous system (the neurobiological mechanisms) that makes the experience of pain possible, and then there is the narrowing of the space around the nerve root (the cause of the pain). Let’s consider two patients with depression. The first is someone who has recently had a stroke and has a textbook presentation of post-stroke depression. Here we can distinguish between the subjective experience of mood alterations, the neurobiology of mood regulation, and how that neurobiology is disrupted by the stroke. The second patient is someone who is experiencing a severe depressive episode after a divorce, and here we can distinguish between the subjective experience of mood alterations (and other symptoms), the neurobiological and psychological mechanisms that are associated with those experiences, the relationship between those experiences and divorce as a life event, and other risk factors that predispose the individual to experiencing depression. It is clear to me that the mere fact of altered subjective experience doesn’t tell us much about the relevant mechanisms, causes, and risk factors. Are you suggesting that the mechanisms and causes that are associated with any experience of illness can be neatly packaged into “mind problems” (mental mechanisms and mental causes?) and “body problems” (neurophysiological mechanisms and neurophysiological causes)? If that is the case, I don’t see what justifies such a binary packaging and why we should accept it.  

More fundamentally, it is not clear to me here what a “mind problem” exactly is. Psychiatric disorders or mental disorders are disorders that have “distinctive features [that] can be adequately characterized only by using the vocabulary of the mental” (Broome and Bortolotti, 2009) but acknowledging so doesn’t take away the fact that psychiatric disorders involve psychological as well as neurophysiological mechanisms, causes, and risk factors. Is there a “mind problem” that doesn’t involve neurophysiological mechanisms, causes, and risk factors? What are we talking about here?

Aftab: Is there a “mind problem” that doesn’t involve neurophysiological mechanisms, causes, and risk factors? What are we talking about here?

O’Leary: I think it’s important, as you say, to clarify what I’m saying with the idea that mind problems are different from body problems. First, we can recognize the difference between them and still notice that their interaction can be complex. In fact, the idea of interaction is incoherent if we don’t begin with two distinct things that can interact. Second, the distinction in no way implies that mind problems and body problems “can be neatly packaged”, as you put it, in practice. It may be that in many cases where the two kinds of problems interact, clinicians are unable to disentangle them. This is no basis at all for imagining that it’s actually a bad idea to try to be clear about the nature of the problem at hand. At this time, many clinicians believe that they should walk away from the diagnostic process as soon as they get near the mind-body line. That idea is incoherent, and dangerous, and patients gain nothing from it. They gain from clinical awareness of complex interactions between mind problems and body problems—and that awareness is impossible without a distinction between them. 

O’Leary: At this time, many clinicians believe that they should walk away from the diagnostic process as soon as they get near the mind-body line. That idea is incoherent, and dangerous, and patients gain nothing from it. They gain from clinical awareness of complex interactions between mind problems and body problems—and that awareness is impossible without a distinction between them. 

You’ve basically articulated a kind of mind-body stew, a list of the many ways that mind and body are related in psychiatry, as if this suggests that effort to better understand is actually a bad idea. I just don’t see any basis for the leap from “we don’t understand it” to “it’s a bad idea to try to understand it”. Further, there’s a simple tool from philosophy that can draw us out of the stew into much clearer territory. As property dualists we agree that there are states of subjective experience, and these are correlated with, but different from, brain states. If we keep that simple picture in mind, we can rely on this basic distinction: mind problems are caused by brain states correlated with experience, while brain problems are caused by brain states not correlated with experience. (My webinar for the Philosophy of Psychiatry series offers diagrams that make this easier to understand.) In a nutshell, as long as we’re clear that all experiences are correlated with brain states, we might say that mind problems are caused by experience, while body problems are caused by purely biological states.

This simple clarification gives us at least one consistent, science-friendly way to understand the difference between mind problems and body problems. More than that, it allows us to locate problems in the realm of the mental (with Bortolotti and Broome) without ever losing sight of the fact that the brain is always involved. So, delusion is subjective experience correlated with a brain state, and pain is subjective experience correlated with a brain state. We might be inclined to toss up our hands there, concluding that there’s just no difference between them, but that conclusion is not supported. There is a difference.

Generally speaking, delusion is caused by a brain state (a kind of body state) that’s correlated with experience, perhaps a trauma, while pain is caused by a body state all on its own, like lumbar radiculopathy. Of course, there are exceptions to these rules, and we can easily make sense of them. Some cases of delusion are body problems because they’re caused by brain pathologies or other bodily pathologies all on their own, and some cases of pain are mind problems because they’re caused by brain states correlated with experience. Moreover, there are many cases of delusion, and many cases of pain, where the interplay between mind problems and body problems is so complex that we can’t possibly sort out which one is doing the most work. All of this is consistent with the picture we get from property dualism. We’ll need at least one more stipulation to handle the hardest cases, but this much, I think, is clear: property dualism provides an objective, science-based way to understand the difference between mind problems and body problems while staying true to the aims of biopsychosocial medicine.

I think much of the resistance to clarity about mind problems vs body problems, arises from concern that if we see mind problems as wholly mental matters, then psychiatry really won’t belong in medicine, or in science. This worry is unfounded. Property dualism does not suggest that mind problems are wholly mental matters. On the contrary, it’s a tool for understanding how to work with subjective experience in the context of brain science. Whether we choose to understand mental disorders within, or outside of, the frame of medicine, property dualism will consistently demand reflection on the role of the brain. It’s the best tool we have for making sense of psychiatry’s ability to plant one foot in the realm of experience and the other in the realm of physical science.

Aftab: Thank you!

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