“If you laid all philosophers end-to-end it would be a
good thing.” Anonymous philosopher
lecturing medical students somewhere in the Midwest in the 1980s.
This post is a partial commentary on a paper about the
philosophy of psychiatry (1) that was recently published. Since I am not a philosopher and do not
aspire to be one – I thank the authors for commenting on what they believe the
key issues and limitations are. Over the years I have written about
philosophical conjecture about psychiatry and consider much of it to be serious
overreach. This paper will allow me to make some general observations. The authors in this case have all published
previous work on the subject and given the number of co-authors this is
considered a state-of-the art review. The review is open access and can be read at
the link in the reference.
In their introduction the authors – consider metaphysical,
epistemological, and ethical issues to be critical at the grey zone between
medicine and philosophy. They mention
Karl Jaspers as a seminal figure in the field but emphasize their focus in the
paper will be on conceptual competence defined as: “the transformative
awareness of the ways by which background conceptual assumptions held by
clinicians, patients, and society influence and shape aspects of clinical care”
(2). To their credit they explicitly
comment on controversies about what the parameters of good philosophy are and
whether progress is made over time.
Their first point is on the boundaries of disorder. They make the usual observations about
Kraepelinian and neo-Kraepelinian and conclude that “neo-Kraepelinians (NKs)
claimed that precisely defined diagnostic criteria could be used to discover
the specific biological causes of psychiatric syndromes and establish
psychiatry as a branch of medicine.” There
is plenty of evidence that the NKs were much more sophisticated than that. From one of their references (3):
“The medical model is not based on any assumptions about
etiology. It can accept social and psychological causes as well as physical and
chemical events. It can accept single
causes or multiple causes. It can even
be applied when the etiology is unknown as in many clinical investigations.”
Guze specifies in several places that the diagnosis is for
describing what is known about the patient and treatment planning. He suggests
that medicine and psychiatry may evolve to provide more information on
pathophysiology and testing but does not link it to diagnostic criteria apart
from how it might be studied. He does not suggest that biological causes are
necessary to establish psychiatry as a branch of medicine – his entire
monograph is about why psychiatry is already a branch of medicine.
The next transition is to Insel and the RDoC. The criticism seems to be that Insel was
criticizing biological psychiatry but I doubt that any biological psychiatrist
would see translational neuroscience as being inconsistent with a brain and
biological centric psychiatry. The field is described as “lurching from one
model to another”. Excluding
homosexuality as a diagnosis is given as a notable example of diagnostic
controversy rather than psychiatry (specifically Spitzer) getting it right and
leading society in general by about 40 years.
There are still plenty of people who have not caught up.
The first main section of their paper is the nature of
mental illnesses. They define strong
naturalism as the factual and value free description of a disorder like
what occurs in the natural sciences. They equate biological psychiatry with
neurobiological dysfunction – even though those psychiatrists clearly had a
much more sophisticated view of psychopathology. I have quoted their reference to Guze above –
here is an additional quote from prominent biological psychiatrists of the 20th
century:
“It should be emphasized…that the demonstration of…[a
catecholamine] abnormality would not necessarily imply a genetic or
constitutional, rather than an environmental or psychological, etiology of
depression…it is equally conceivable that early experiences of the infant or
child may cause enduring biochemical changes and that these may predispose some
individuals to depressions in adulthood…[and] any comprehensive formulation of
the physiology of affective state will have to include many other concomitant biochemical,
physiological, and psychological factors.” (4)
That sounds like pluralism rather than naturalism to
me. There are several additional factors
that suggest that the idea of strong naturalism is an exaggeration of the
position of late 20th century biological psychiatrists. Some of those factors include: the concept of
heterogeneity in diagnostic categories was widely known at the time,
endophenotyping was introduced in 1966 as a purely biological concept (5) that
was later applied to medicine and psychiatry (6). Clinical trialists were certainly aware of
heterogeneity and significant problems with recruiting patients into studies
based on severity and placebo response.
The general comparison to medical conditions where a significant portion
were idiopathic and had speculative pathogenesis and to this day are still
diagnosed based on clinical description is an additional factor. Any intern on medicine or surgery knows
pathophysiology and the suggested mechanism of action of medications is typically
speculative and no two patients with the same diagnosis are exactly alike. A key concept in training is that physicians
are required to recognize that pattern and make the necessary adaptations.
The authors introduce the definition of strong
normativism as basically “no natural, objectively describable set of
biological processes that we can characterize as “dysfunctional”, and hence
disorder attributions are thoroughly value-laden.” They do not elaborate – but this definition
is clearly counter to the experience of any physician who has treated life
threatening or severe illnesses.
Szasz is introduced at that point because of his suggestion
that mental illnesses do not exist but rather represent “judgments of deviance
based on sociocultural norms”. They
suggest that he is both a strong normativist and a strong naturalist
rather than just being wrong. Szasz’s
philosophy (if that is what it was) fails several tests, but for the purpose of
this post is probably the best example of controlling the premise rhetoric to
prove a point. The Szasz definition of disease
as actual observable pathology allows him to trivialize any condition not
meeting that criterion (and there are probably more outside of psychiatry than
within) and call it a value judgment. That is not consistent with diagnostic systems
present before him or what historical neuropathologists thought (7).
What follows is a section on the naturalist-normativist
debate including a table of the contrasting points. The basic problem with
this dichotomy is that the normativist position as described by the authors is
such a caricature when compared with medical and psychiatric training that it
really cannot be seen as a viable position by anyone but Szasz. They produce a couple of examples of hybrid
positions as though they have never been considered in the past. The description of Wakefield’s suggestion
that dysfunction that is harmful to the individual is required for
disorder, but since depression is an evolutionary response to adversity it is
not dysfunction. That ignores empirical
research that suggests that it can be both as well as the problems associated
with speculation in evolutionary psychology. The discussion of values in the
normative model leaves out a lot and ignores psychiatric training. If the goal is
to inform psychiatric practice by this kind of debate there are better ways to
go. Psychiatrists walk into the room with a patient and their goal is to
understand that patient well and treat that patient well. That involves
communication skill, developing a therapeutic alliance, therapeutic neutrality,
and providing the patient with enough information so that they can provide
informed consent. That interaction is
both scientifically and professionally informed.
The next concept the authors discuss is essentialism
or the idea that naturally occurring kinds have an evident essence. They
acknowledge that when it comes to medical disorders straightforward
classification is generally problematic but for some reason it is more
problematic for psychiatry. They suggest that:
“If psychiatric classifications such as the DSM and the
ICD were demarcating natural kinds, we would expect each diagnosis to
correspond to an entity that exists in the structure of the world, independent
of human interests.”
That quote misses the mark at a couple of levels. First, a classification system is really not
a diagnosis. It is more of a hypothesis and general locator (8). The diagnosis
takes additional information including some of the validators that they
minimize in this section. Second, in looking at these features it is obvious
that many of the big ones – like mania “exist in the world independent of human
interests.” They have after all been
described since ancient times across multiple diagnostic systems – long before
there were psychiatrists. The same is
true of melancholia and several other disorders. Granted – there was no DSM
back then but I cannot think of better evidence that there are natural kinds by
this definition that have been updated. Third, it should be obvious that many
disorders are clearly there for research purposes and this is evidenced by the
fact that only about 50% of the diagnoses are used on a clinical basis and many
psychiatrists attest to the fact that they doubt a single case of specific
disorders exist (9,10). Finally, essentialism in biology became a casualty of evolution. Prior to Darwin, Linnaeus suggested that species were distinct and unchanging entities created by God. That is an essentialist position. Evolutionary theory changed all of that because species change based on individual variation and new species occur (11).
Whenever I read about the philosophical concepts behind what
constitutes psychiatric illness and classification – I am always left
considering why philosophy is prioritized over biology. Medicine is after all firmly rooted in human
biology. There is no better evidence
than the biochemistry, anatomy, and physiology courses taken in medical school
basic science. Biology provides a
framework for both hierarchical organization as well as individual
classification of diseases including mental disorders (see lead graphic).
Modern taxonomic classifications of both date back to the mid -18th
century.
A critical question is whether biological classification has
advanced to the point where it is not controversial and purely scientific. The short answer is no. There is ample
evidence that the taxonomy of living organisms is problematic and there are ongoing controversies over the past 50 years. Although species is a fundamental
organizational concept in the field of biology that has not prevented the
proliferation of up to 24 different species concepts in recent times (12). Why would medicine be expected to have a more clearly defined classification system than biology?
Rather than comment on the remaining sections that I am sure
that I also have problems with – I am going to introduce and idea that I have
not seen written about anywhere. If you
read this an think I am wrong please let me know and send references. That idea is the application of biological
theory to psychiatry. Medicine and psychiatry are after all firmly based in
human biology and human biology is a subset of biology in general. When you attend medical school and complete all
the basic science training this basic fact is explicit. There is not much
discussion of other organisms unless they happen to be pathogens. There is also not much discussion of the
levels of organization in human biology and the implications that has for
medicine.
What does the tremendous complexity of biology have to do
with psychiatry? It is evident that various mechanisms make it very difficult
to classify biological organisms. That
has resulted in many species concepts and that array of concepts has complicate
taxonomy at a time when the biodiversity of the planet remains inadequately
characterized. Psychiatry is operating only in one species by the same
mechanisms that complicate biology at all levels also complicate biology. To the purpose of this essay the critical
question is why they currently seem less important than the increasing presence
of philosophy in psychiatry. Frequently the justification seems to be the old
quote about “carving nature at the joints.”
Does that mean we philosophize about it and maintain endless
arguments? Or does it mean we consider
that human beings and their mental disorders are based in human biology and try
to make sense of it by studying biological principles. And by biological principles – I don’t mean
the typical jargon of biological psychiatry used by critics. I mean theoretical
biology practiced by biologists.
I want to touch on just two concepts from biology that have
implications for psychiatric controversies.
The first are the classification systems in biology and the second is
stochastics. There are any number of
authors offering descriptions about how psychiatry has evolved in the last 200
years. That generally tracing the origins back to 19th century
European schools of thought and bringing those threads forward. The focus is generally on nosology including
diagnostic systems, treatment settings, and how treatments evolved. The brief discussion of biological
classification here touches on a large literature that has been ignored by
medicine and psychiatry. In the debate
of categorical versus dimensional diagnoses and the various philosophical
labels a significant number of biological classifiers have been left out.
If I am correct what might have caused this significant
omission? First, the focus of medicine has been description based on
clinical findings. I have used this
characterization previously:
"For several thousand years physicians have recorded
observations and studies about their patients.
In the accumulating facts they have recognized patterns of disordered
bodily functions and structures as well as forms of mental aberration. When such categories were sufficiently
distinctive, they were termed diseases and given specific names. “
DeGowan and DeGowan, Bedside Diagnostic Examination. 1976, p
1
That has been the historical and primary focus of medicine.
Interest in pathogenesis happened in the 19th century but even then,
there were conditions that that escaped that classification. There has been progress there are still many
conditions with no clear pathophysiology and even fewer medications where the
mechanism of action is known. One of the primary reasons is that medicine has
been based on reductionist biology and even though advances have been made it
seems to have reached its limit. What do I mean by reductionist biology? Simply put it means breaking down complex
systems to component parts and studying those parts independently. In current jargon it has also been referred
to as a bottom-up approach. Second
– biological psychiatry is biological in the reductive scientific sense
and it needs to be biological in the integrative sense. All biology is
not reductive (17,18) – but much of the philosophy I have read seems to think
so. Reductive approaches have led to
discrete research programs that produce highly speculative connections to
psychiatric disorders. We end up with biological psychiatry as neurochemistry
-> neuroendocrinology -> neuroimaging -> genomes, connectomes,
proteomes, transcriptomes, metabolomes, etc without any clear underlying
connection to all human biology. Systems
biology or network medicine approaches have been used on only a partial basis
so far. Third, rather than make a
truly biological connection the field seems to have been sidetracked by
philosophy. Much of that philosophy has
been around for 50 years or more and seems satisfied with the role of asking
questions and never really providing much of an answer. Much of the philosophy is vague and untestable. A secondary role seems to be the criticism of
psychiatry with a dependence more on political rhetoric than reality.
Conclusion:
When philosophers criticize medicine and psychiatry, they
frequently use the term constructs. From
a rhetorical perspective not, all constructs are alike. In medicine and biology there needs to be at
least some real-world observable basis.
Rather than strong arguments for philosophy in psychiatry –
the authors have argued strongly. I have tried to elucidate the rhetoric
involved since my observation is that is the nature of most philosophical
arguments directed at psychiatry. The
curious aspect is that most people do not even consider this when reading
philosophers commenting on psychiatry. I
sent one of my papers to a friend who has been a psychiatrist as long as I have
and he told me that he never considered it an area for analysis. I hope that
some of the comments here are useful in considering these arguments and why
they should not be blindly accepted.
It seems that in all the philosophical criticism and
discussion of psychiatry, van Fraassen's empirical adequacy has been
ignored (16, 17). The reasons for that
may be less than obvious. Van Frassen
basically states that an empirically adequate model is just that – it is not a
comment on the truth of existence or not.
There is a question of whether the model must be based on direct
observation. The criteria for mental
disorders require reporting subjective states that are not directly observable.
Van Fraassen’s theory includes the outcomes of experiments and isomorphic
models – both of which apply to work in psychiatric nosology. The lack of
comment on Van Fraasen’s approach is critical because it reflects how
psychiatrists are actually trained and directly counters arguments about positivism
and realism. Some references suggest that what appear to be
diametrically opposed arguments in philosophy are just sustained with no
resolution and that is a significant limiting factor when considering what
psychiatrists need to know.
Not all biology is reductionist and not all philosophy is useful. Empirical adequacy and biological complexity are the future
of psychiatry.
George Dawson, MD, DFAPA
References:
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Dedication:
This post is dedicated to my undergraduate biology Professors at
Northland College including Lee Stadnyk, Richard Verch, John Brennan, and
Mallanpali Rao. I spent many months studying the comparative anatomy and physiology of
invertebrates and the taxonomy and population dynamics of sphagnum moss plant
species, aquatic invertebrates, and freshwater plankton with these professors
and they were the best. I also had the
pleasure of working on Loblolly Pine (Pinus taeda) and Douglas Fir (Pseudotsuga
menziesii) species in Don Durzan’s lab at the Institute of Paper Chemistry.
Experience in biology is a grounding in the complexity of living organisms.
