In a recent article in this journal, Henry and his coauthors1 argued that Michael Polanyi's philosophy of Tacit Knowing should replace evidence-based medicine (EBM) as the new epistemology in medicine. They argued that incorporating the epistemology embraced in Tacit Knowing would free the physician from the unreasonable demands imposed by the quantitative orientation of EBM. Unfettered by the rigors of the analytic framework of EBM, the physician could rediscover the human dimensions perceived to be lacking in the current practice of medicine.
However, my misprision (defined below) of Polanyi did not reveal a philosophy of knowing that resided in the subjective alone, but was firmly embedded in a rich scientific tradition, complete with all of the methodological requirements of that tradition.2 Professor Polanyi recognized the sedimented layers of this scientific tradition for new insights must, in and of themselves, be laid within a community of scientists who provided the peer-based cement that ensured that all subsequent developments would have a secure foundation.
Just as Polanyi would not accept assertions about truth based solely on faith, neither should we accept the claims made by Henry and his coauthors1 that Tacit Knowing is the critical epistemological piece missing in the practice of medicine without careful consideration. In this article I explore these claims more fully and suggest possible different directions that may be more consistent with these authors' goal of humanizing the clinical encounter and, ultimately, more fruitful to the practice and teaching of medicine.
The overall genius of Michael Polanyi (1891–1976) is not in question, given his many contributions in the fields of physical chemistry, economic and political philosophy, and the philosophy of science during the first part of the 20th century.3 Had he continued in the field of physical chemistry, his first academic endeavor, it is generally believed that his efforts in that field would have been Nobel worthy, but he remolded himself to become a major thinker, albeit always an outsider, in the field of philosophy. It has been argued that his “outsider” status in the field may have led to some of his most profound insights in these areas because he was unfettered by the encamped traditions within these areas of scholarship that were new to him.
A major paradigm in the history of the philosophy of science was the school of logical positivism, the fundamental premise of which is that the truth worth knowing through the scientific method is objective, empirically based, and verifiable (or at least falsifiable). According to this theory, the truth stands alone without any need for a supporting tradition. Polanyi correctly and singularly rejected this thesis in arguing that all knowing involves engaging the subjective with that which is to be known. Although carefully developing his epistemology to avoid the charges of solipsism and relativity, Polanyi made the compelling argument that the subjective is a critical element in the process of discovery. He also elaborated the theory of Tacit Knowing that deals with those subsidiary elements of one's “knowing” that can never be articulated but that, nonetheless, are essential to the knowing of the thing to be known. The concepts of Tacit Knowing and Personal Knowledge in science are not an epistemology that stands alone; instead, insights gained from one's own Tacit Knowing are subject to the evaluative methods of the community of scientists who are part of the collective scientific process. This interaction is defined as Polanyi's fiduciary program, which I discuss further below. Polanyi laid the foundation for the work of other philosophers of science, such as Thomas Kuhn,4 in firmly and convincingly arguing that any scientific claim is subject to the rigorous testing and evaluation of one's peers. Thus, the worlds of scientific paradigms and revolutions were born.
My Misprision of Polanyi
Before advocating the application of a new paradigm to replace EBM, one must be absolutely clear about what is embodied in that new perspective. Crossing the language and meaning chasm between medicine and philosophy is a dangerous journey. In this article, I use the term misprision as it is presented in the work of Harold Bloom.5 So used, this term reflects the difficulty in understanding, reinterpreting, and introducing someone else's theory or ideas, and the necessary deviation from the original intent, for better or worse. What follows is my misprision of Polanyi's theory, borrowing deeply from a number of sources.6,7
Polanyi elaborated his theory of Tacit Knowing in response to the prevailing paradigm of objectivism or logical positivism in the early part of the 20th century. The latter theories embraced a worldview that all knowledge exists outside the observer or scientific community. Polanyi rejected that view and argued correctly that knowing is an intentional act—on the part of the scientist, for example, toward the item of inquiry within an established scientific community.1,7–9 This process of knowing involves elements made of subsidiary and focal components, both of which are tacit; that is, they cannot be explicated in the process of knowing. These elements include, for example, an informed intuition, a Gestalt judgment, and a Eureka moment. Polanyi held that this process of knowing was an art and, as with any art, must be learned through an apprenticeship model and practice. Rules of an art can be useful, but they do not determine the practice of that art. In other words, deconstruction of an artist's method (e.g., the practice of medicine) can be analyzed for insights into how one practices medicine, but the actual practice of medicine can never be seen as a simple reconstruction of this deconstructed model.
Take, for instance, riding a motorcycle. One can list all the specific parts and processes, including the brakes and the distribution of forces between the front and rear, the clutch, the gears, and the weight shifting in navigating hairpin turns, but reconstruction of these elements would not help a novice to climb on a motorcycle and successfully ride it through a challenging journey. A rider negotiating hairpin turns focuses his or her attention on a distant point in the road, not on all the particulars of the actual process. The rider must be connected through the body to the machine in a seamless fluid process that successfully accomplishes the maneuver. Any complicated physical or mental endeavor requires the same freedom from attending to the particulars of the art. In this respect, practicing medicine is no different from swinging a golf club, riding a motorcycle, or solving a scientific puzzle. True artists can rarely deconstruct in the moment the particulars of the process that led to a successful outcome, and, if they tried, they would proverbially fall off the motorcycle. Polanyi suggested that the process of knowing is made up of subsidiary foci that can never be known and which operate within the perspective of the observer.
Polanyi used Gestalt judgment as a metaphor for the summative experience of combining the subsidiary and focal elements, leading to the moment of epiphany. He strongly recommended that anyone interested in learning the process of Tacit Knowing in a chosen field serve as an apprentice to a successful mentor in the student's area of choice. He felt that learning the process in any given field was also accomplished by exposure to and tacit osmotic absorption of a practitioner's methods. I am sure he would have railed against the endless deconstructed curricula that litter the landscapes of modern medical education bookshelves, never dog eared or pertinent to the actual learning of the art.
Stages of discovery
In the process of Tacit Knowing, Polanyi adapted four stages of discovery: preparation, incubation, illumination, and verification.1 Although a detailed discussion of these stages is beyond the scope of this article, it is within the stages of incubation and illumination that the insights from Tacit Knowing are operative. The creative process of knowing a new truth requires an element that can never be fully elucidated. The verification stage is also particularly important because any attempt at verifying the scientific or clinical truth requires an appeal to a traditional scientific community and its evidentiary rules for causation. Polanyi would shudder at the claim that a simple assertion of truth is alone sufficient without subjecting the alleged truth to scrutiny in relation to the rules of the scientific community. In the realm of clinical decision making, EBM is the keeper of the rules that would be used to assess the truth of a clinician's assertion about diagnostic or therapeutic claims made by the practitioners. Polanyi was, first and foremost, a scientist who firmly embraced the concept that any scientific truth is grounded in the established traditions. Thus, the assertion that EBM—an established tradition in the realm of medical education—should be eliminated as an important epistemological practice would violate one of Polanyi's central premises.
Polanyi's fiduciary program
One of Polanyi's great contributions to the philosophy of science was to define the role of the subjective (or personal belief) in understanding the world and in acknowledging the important traditions within a specific field that are used to verify asserted truths. Tacit Knowing, according to Polanyi, requires affiliation with a like-minded community. Polanyi argued that “no intelligence, however critical or original, can operate outside such a fiduciary framework.”2 Polanyi attempted to show that the practice of science actually depends on both tradition and the authority exercised by a community of practicing scientists, but he also understood that such authority can be tyrannical and destructive to the ongoing scientific process. He personally experienced this tyranny when one of his discoveries was rejected by the scientific community because conceptual models to support his reported data had yet to exist. Nonetheless, he accepted the verdict of his peers only to be vindicated subsequently when his scientific claims were supported.7
The Straw Man of EBM/Clinical Epidemiology
Henry and his coauthors1 assert that the EBM “movement” is well known and controversial. Because of its heavy focus on quantitative analysis, the authors claim that EBM suffers from an epistemological deficiency and that EBM methods cannot accommodate concepts that resist quantitative analysis. Furthermore, they argue that EBM cannot differentiate human beings from complex machines. This classic example of a straw man argument does not address the well-known limitations of EBM, nor does it address the scientific and historical reasons for the development of the whole endeavor encompassing health care research, clinical epidemiology, EBM, and the decision sciences. Of great interest, the authors cite Alvin Feinstein as a “godfather of EBM” and as being highly critical of physicians and researchers for analyzing medical practice using simplistic quantitative models that were not developed from clinical experience and observation. As one of Feinstein's former fellows, I can assure you that his epistemology was firmly quantitative through and through, though he advocated more sophisticated quantitative models than those he criticized. I cannot imagine him embracing a qualitative method. His landmark four-article series in the Annals of Internal Medicine that later became his book, Clinical Judgment, laid the groundwork for exploring a richer quantitative framework for outcome-based research that eventually led to the use of quality-of-life indices, functional assessment, quality-adjusted life years, to name a few quantitative measurements attributed to him.10–14 In a later misunderstood and misquoted article, Feinstein argued not for qualitative models of research, as is often thought, but for better quantitative models.15 But, more important than misinterpreting Feinstein's perspective on the issue, blaming EBM for the current humanistic crisis (as presented in the article by Henry and his coauthors1) in medicine is like blaming the Archduke Franz Ferdinand for getting in the way of the bullet of Gavrilo Princip and starting World War I. There are so many other forces that shift our gaze from the patient as person and prevent us from truly practicing patient-centered care that it is hard to know where one should start to parcel blame. The insurers, Centers for Medicare and Medicaid Services, the tort system, huge bureaucratic health systems, profits, margins, and income targets all obliterate the patient from the true center of care. Any epistemology that would revert the current moral inversion in the clinical sphere, to use a Polanyian term, would be welcomed by all health care givers. However, eliminating EBM would certainly not lead to the desired goals of humanizing medicine. I am sure that Professors Polanyi and Feinstein would not only be rolling over in their graves if they heard such a suggestion, they would be rotating at 60 cycles per minute.
Goals of EBM
The field of EBM is relatively new to the enterprise of medicine, and it developed to provide a framework for analyzing the available medical research. The JAMA Users' Guide to the Medical Literature 16 presents two fundamental principles of EBM. First, as a distinctive approach to patient care, EBM is never sufficient to make a clinical decision. Decision-makers must always trade the benefits and risks, inconvenience, and costs associated with alternative management strategies, and in doing so consider the patient's values. Second, EBM posits a hierarchy of evidence to guide clinical decision making. Thus, knowing the tools of evidence-based practice is necessary but not sufficient for delivering the highest quality patient care. In addition to clinical expertise, the clinician requires compassion, sensitive listening skills, and broad perspectives from the humanities and social sciences. These attributes allow understanding of patients' illnesses in the context of their experience, personalities, and cultures.
As with any straw man argument, Henry and colleagues1 correctly describe, as have others, the current scientistic trend to embrace EBM as the only relevant science that should dictate clinical decisions. My use of the term scientistic is intentionally pejorative and is meant to convey a need for a midcourse pendulum shift away from the belief that the methods of EBM should dominate the focus at the bedside. The patient as person, as stated by the authors, should remain the physician's primary focus at all times, and along the same lines, the physician should consider other disciplines, including behavioral medicine and humanities, for example, while treating the patient. It is not so long ago that another “godfather of EBM,” Dr. David Sackett, and his coauthors17 dedicated their first book of clinical epidemiology to the emperor's new clothes (in addition to H.L. Mencken, Kurt Vonnegut, Jr., and Douglas Adams). I always interpreted this humorous dedication as a warning to all practitioners of EBM to avoid the grievous sin of malignant hubris, that is, taking themselves or their models too seriously. This dedication was not included in subsequent editions, and I always wondered whether that deletion occurred because they believed that the invisible clothes were no longer new, that the EBM discipline had fulfilled its promise, or the authors had lost their sense of humor. I hope it was not the latter.
Given the current emphasis on preventing medical errors, increasing patient safety, and enhancing health care quality, the future of medical practice and education requires the foundation of knowledge provided by the areas included in EBM. Henry et al should not seek to extricate this epistemology, because it may be somewhat futile given current paradigmatic realities. However, a shift in educational focus from EBM to the patient is becoming a central tenet of the patient safety “movement,” which should give some solace to the authors' epistemological dreams. This is not the article, and I am not the author to review this movement, but any Medline search on clinical decision making; patient safety, quality, and errors; intuitive judgments; etc.; will keep you quite busy for some time.
Evaluation of Tacit Knowing
Henry and colleagues1 state that “Tacit Knowing is certainly not infallible, and misleading Tacit Knowing is, by its nature, harder to recognize than faulty conclusions from clinical trials or clinical experience.”1 In my opinion, Einhorn and Hogwarth18 address this topic well when they discuss the question, “Can we learn from experience that we cannot learn from experience?” Einhorn and Hogwarth's major thesis is that individuals often lack the conceptual framework to analyze their experiences, often missing the false-positives and false-negatives and overweighting the true positives in their personal experience. Henry et al need to better appreciate the value of the “quantitative” method in evaluating the outcomes of Tacit Knowing; they confuse the process (how one reaches a real insight that may not be reducible to a list of variables to be regressed in a multivariate model) of Tacit Knowing with the outcome (whether a diagnosis is present or a prescribed treatment is efficacious). The latter truths asserted by the “tacit knower” can be subjected to the same methodological criteria suitable for any diagnostic or therapeutic evaluation. To borrow the clinical epidemiology term generalizability, the clinical or scientific insights gained from one's Tacit Knowing may be different depending on the individual and his or her knowledge base, cognitive skill, and intuitive senses, and, therefore, they may not be generalizable in a variety of experiences, both clinical and otherwise (see the discussion of the stages of discovery above). In fact, probably most clinicians do not have the potential for categorization as “expert decision makers,” “Nobel-level scientists,” or any other term describing those truly gifted thinkers. The EBM literature is replete with examples of how poorly some of us analyze the clinical data before us.19–22 That I use the subsidiary elements in my Tacit Knowing in the everyday experience of recognizing a friend on the street, for example, does not free me from critical evaluation of my clinical judgment and its very real outcomes—survival, death, and quality of my patient's health care. Henry and his coauthors1 make a bold claim that “EBM's formal rules are consistently inadequate not because they lack sufficient detail, but because many medical concepts cannot be explained within EBM's epistemological framework….” They go on to argue that “we suggest the need for an expanded and reworked epistemology of clinical practice that moves beyond EBM and its current beliefs about medical knowledge….Polanyi's philosophy of Tacit Knowing provides one useful starting point for building such an epistemology….” However, my misprision of Polanyi suggests that the philosopher always grounded his theory of Tacit Knowing within a larger scientific community that would prevent the very relativism inherent in the argument proffered by Henry and his coauthors. Any argument for the central role of Tacit Knowing in the epistemology of medical practice should be supported by compelling data presented using quantitative and qualitative evidentiary standards defined within the scientific clinical community. I would argue Michael Polanyi would make the same demands, and the authors have not provided any research references to support their faith-based claim.23
Suggestions Made Most Humbly
There are many elements in Polanyi's work that could be of great benefit to the teaching and practice of medicine. His major insight into the process of Tacit Knowing and its implication for how we teach students, residents, and practicing physicians could and should inform how we create and evaluate learners along the clinical spectrum. His emphasis on the apprenticeship model of training is especially relevant and embraced by both Henry et al and me. Using the patient as the primary center of learning is critical and has tremendous implications for those educators who see simulations as a primary mode of training. There is enormous research potential in evaluating the efficacy of patient-centered versus simulator-centered training. The educational experiences of students and residents have shifted away from the patient at the bedside (or at the examining table in the outpatient setting) to conference rooms, and these experiences focus on computers, interactive programs, and simulation systems that are logistically easier to create than the high-quality tutoring experience that occurs within the clinical relationship. Most learners may only rarely be seen actually providing care, and the supervising faculty may be more interested in completing work tasks than in providing educational experiences for the learners. Even more rarely is the pivotal role of the patient as teacher realized within clinical educational environments. The current clinical educational model is in need of a serious overhaul.
Many years ago, Professors Maurice Natanson and Marjorie Grene pointed me, their apprentice, in a different direction than Polanyi and his theory of Tacit Knowing as I struggled with the many challenges within medical education. It has taken me almost 30 years of thinking and reading in their recommended field of phenomenology to explore how one could rediscover the truths of the lived realities of being a patient, a physician, or a student in medicine, of dealing with life and death, working in dysfunctional health care systems, exploring meaning for patient and caregivers, or redefining one's self after serious illness, just to name a few. What is wrong with medicine is not the loudness of EBM but the silence of any research and writing dealing with these very important issues of human meaning within the clinical world.
Henry and his coauthors,1 as well as many other observers of clinical educational experiences, have argued for an epistemological shift from EBM to a new model, to rediscover the humanistic element in the clinical encounter. In my experience, shifting paradigms or epistemologies is not so easy, and, as argued above, such a shift in this situation is misguided at best. EBM serves us well in dealing with its limited analytic goals, but more robust educational methods are necessary to demonstrate those sedimented essences alluded to by Henry et al and others. Many scholars studying the humanistic component in the clinical encounter have come form a variety of traditions, such as phenomenology, narrative medicine, ethnomethodological research, case study analysis, and others.24–33 The goals of these efforts are to explicate the human meaning within the experiences in medicine, to address questions about what it means to be a patient, be a clinician, have an illness, or recover from that illness, and a number of other vital topics essential for students of medicine to appreciate if they are really destined to become good doctors. Unlike Henry et al, I would argue the more serious crisis is ontologic (i.e., the explication of meaning and being), not epistemologic (i.e., the process of knowing).
Notes on the methods
Any attempt to recover the humanistic element in the clinical encounter will require the expansion of research methods beyond the usual quantitative models. The rich descriptive narratives that convey the essence of the lived experiences of patients and clinicians need to be generated and appreciated in every academic environment if we are to reestablish the importance of the personal in the clinical encounter. An exposition of the many methods available to accomplish the above is beyond the limits of this paper (and most likely this author), but most methods (e.g., the narrative method as described by Charon,28 the case study method developed by Robert Stake,32 the ethnomethodological method from sociology, the phenomenologic method as described by Zaner26—to name a few) use rich immersion and description techniques to capture the meanings embedded within medicine that I have described above.
For the kind of change envisioned by Henry and his coauthors,1 the research and clinical mission would have to be extensive. That rich descriptions of meaning in medicine within fictional and nonfictional literature already exist is not sufficient to accomplish the above. We have to prioritize these discussions within every clinical environment, and the experience of the learners (students, residents, faculty), in part, serve as the rich research strata for producing the above descriptions. In other words, one cannot expect a learner to read The Death of Ivan Ilych and appreciate its meaning as it relates to their taking care of patients. The instructor must acknowledge and incorporate the literary experience within the clinical encounter for each learner.
Appreciation of Meaning and the Delta Factor
The challenge for all educators is to enable our learners to truly appreciate the meaning of their experiences with patients. Walker Percy34 captured this meaning in his nonfiction work The Message in the Bottle, where he described the Delta Factor as the integrated appreciation of the meaning within any given context. Using Helen Keller's breakthrough at the water pump as an example, he describes the process by which a learned concept and a lived experience become unified in such a way that the learner has forever changed her worldview. Once one appreciates a meaning at this level, he or she can never go back to a presentient existence. When our learners are exposed to such experiences, we no longer have to teach, because the lesson speaks for itself. It becomes so integrated as to be neurologically hard wired. The current clinical educational environment lacks the analytic paradigms, the protected time, and the trained clinical faculty to create such learning experiences. Achieving the Delta Factor within this current environment is a challenge that simply replacing EBM with Polanyi' s Theory of Tacit Knowing cannot solve.
We need to be shocked out of our “taken-for-granted” worlds in medicine (a concept not dealt with by Polanyi) to realize those dimensions of meaning that humanize the clinical process. My hope is that these new research methods in their dedication to a “Proustian” level of clinical detail will be very useful prisms to see the clinical world in a very different and far richer way.35
The insights of Michael Polanyi are extremely valuable and have laid the foundations for future scholarship in so many areas. His major contribution to clinical medicine may be his theory of Tacit Knowing and the implications for structuring learning and clinical environments for true mastery of the clinical method. EBM does not need to be dethroned for educators to embrace the richness of Polanyi's insights. In fact, as argued above, EBM would play an important scientific role in Polanyi's clinical universe.
As suggested by those intimate with Polanyi's thinking, there may be much richer research and philosophical traditions available to accomplish Henry and colleagues'1 goals of “rehumanizing” the clinical encounter and refocusing the clinical and educational agenda on the patient as person. Only time will tell if a critical mass takes up the challenge and produces the evidence to justify the central role for a humanistic ontology and epistemology in the clinical encounter and convince the many external and internal forces within medicine that this new body of research should inform the future landscapes of clinical medicine and education.
The author would like to thank Todd Ibrahim, Robert Wigton, Michael McFarlane, William Iobst, Doron Schneider, and Richard Eisenstaedt for their comments and support. The author would also like to thank Maurice Natanson, Marjorie Grene, and Alvin Feinstein for providing a rich apprenticeship experience. Finally, the author wishes to thank the two anonymous reviewers and the editorial staff of the journal for their excellent suggestions and for pointing me in a valuable research direction.
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