Has medicine become a science?

Johann Steurer

 

In the nineteenth century, Western medicine was still a prescientific art. Then William Osler gave the basic sciences of medicine a central role in his epoch-making textbook of medicine and brought them to eminence in medical education, and research in those sciences had its first major impact on medicine. Those dramatic, science-based advancements in medicine led to the conception of modern medicine as a science. But in medical academia today there is a major divergence of views about this. We argue that medicine still is, and always will be, purely an art, with medical research extrinsic to it. We delineate the implications of the recognition of this for medical academia.

Hippocratic medicine as a prescientific art

In the Hippocratic conception of medicine, it was an art. Thus, the most widely known of the Hippocratic aphorisms opens with the words “Life is short, the art long...” and in the Hippocratic Oath, each freshly-minted physician swore major commitments to his teacher of “this art.” In this type of usage, our contemporary word ‘art’ denotes the involvement of particular knowledge and skills in the genuine practice of the art in question. The Hippocratic physician was a practitioner of ‘the art of medicine’ in this meaning of ‘art.’

This art was rooted in a profound innovation in the philosophy of medicine, at a time when ‘temple medicine’ was dominant in Greece. It grew out of emancipation from belief in divine healing of illnesses, in which healing was sought from Asclepius himself and/or his daughters (Hygeia and Panacea) in sleep (‘incubation’) in the inner court of one of the numerous temples of this god of medicine. In a radical departure from this, Hippocratic physicians were philosophically committed to practices based on empirical knowledge rationally derived from experience in the practice of the art.

But the substantive foundation of this medicine was, ab initio, antithetical to empiricism; it was doctrinaire rather than empirical. Sickness was viewed as an overt manifestation of ‘imbalance’ among the postulated four ‘humours’ in a person’s body (blood, phlegm, yellow bile and black bile); and for restoration of that balance, bloodletting was considered a virtual panacea.

Outside of Greece, an incomparably influential advocate of that medicine – its bloodletting included – was Galen, who had been highly educated in philosophy and medicine in the Hellenic world, where a very extensive literature on ‘Hippocratic’ medicine had developed. Through his extensive writings in Rome in the second century AD, he became the principal authority in European medicine, a status which lasted throughout the Middle Ages and the Renaissance.

After Galen, Hippocratic bloodletting was famously practiced and propagated by, among others, Thomas Sydenham, the ‘British Hippocrates’ in the seventeenth century, and then, a good century later, even more radically and influentially by Benjamin Rush, the then-preeminent physician in America. Most notable, however, are the recommendations as recently as 1892 of the use of bloodletting (for pneumonia, among others) in the highly-esteemed and for decades very widely-studied textbook of medicine by William Osler [1], in his time the preeminent physician in the world.

Thus, physicians’ experience with bloodletting – over the two millennia of its Hippocratic deployment (following its age-old prior use in Egypt) – did not seriously undermine their faith in the doctrines underpinning its use. And reliance on experience in the practice of medicine as the source of the knowledge needed in the practice of medicine also stood the test of that very long time.

The main point of these historical notes in the present context is that from antiquity all the way to recent modernity, Western medicine was a Hippocratic art – in the Aristotelian sense of the art/technê of human healthcare, distinct from any science/epistêmê (the pursuit of abstract knowledge). Hippocratic medicine was, specifically, a prescientific art.

Science defining post-Hippocratic medicine

Hippocrates and Galen are, unquestionably, eminences of the highest order in the history of Western medicine, and Osler, at least arguably, rounds out the troika of such luminaries.

Thinking and writing about post-Hippocratic medicine was Osler’s sole focus in the first four years of his professorship in the faculty of medicine at the nascent Johns Hopkins University. The result of this major effort was his epoch-making tome The Principles and Practice of Medicine (ca. 1100 pages) [1].

The contents of this landmark text were organised according to a particular taxonomy of illnesses (“diseases”). This taxonomy was a reflection of the fundamental novelty of post-Hippocratic medicine: the humoral doctrine about the essence of illness (singular) was supplanted by knowledge about illnesses – about the pathology (anomalies of structure and/or function) definitional to a large multitude of illnesses, as established by medical science.

Osler did not define the concepts he associated with the terms in that book’s title – “medicine” or the “principles” and “practice” of it. Nor did he otherwise indicate whether he thought of the practice of the post-Hippocratic medicine which the book addressed as still being a prescientific art or a scientific art.

The medical education that Osler introduced at Johns Hopkins was centred on the source of that fundamental novelty in post-Hippocratic medicine. Thus, the basic sciences of medicine were the sole focus of the first two years of the four-year course of education, which followed the required ‘pre-med’ studies in physics, chemistry and biology. The other two years were devoted to medicine proper.

This education was lauded and held as exemplary in the highly influential “Flexner report” of 1910 [2]. In it, Abraham Flexner reported on his review of medical education in the US and Canada. This review was instigated by the American Medical Association (AMA) and implemented under the auspices of the Carnegie Foundation for the Advancement of Teaching.

Flexner’s judgment of the superiority of the education at Johns Hopkins was fully embraced by the AMA, and this education was consequently adopted as the standard in the US. Other countries gradually followed suit, almost universally. Thus, through his signature textbook and the teaching he introduced, Osler gave science an eminent role in medical academia at large, making it Oslerian in its fundamentals. The science with which he was concerned was the aggregate of what we now call the basic sciences of medicine.

Medicine itself becoming seen as science

At the time when Osler was introducing this science-heavy education to medicine, the first major impact of science on the practice of medicine was taking place. It was a two-pronged impact – of science from outside of medical academia and also outside of medicine proper. It was not the availability of new knowledge for deployment in the practice of medicine. Rather, the novelty was the availability of new products and processes for use in medicine.

There was, for one, the impact of the biological research of Louis Pasteur and Robert Koch. Knowledge from this research had become ‘basic’ to the development of highly effective (and reasonably safe) vaccines for epidemiological use and for preventive medicine of the clinical variety, too. And for another, chemical research in the then-incipient pharmaceutical industry had provided for the development of therapeutic and palliative medications – one of which was aspirin – for use in clinical medicine.

These dramatic advancements in medicine, resulting from medical research, gave rise to common conception of modern medicine as a science. This novel idea substantially enhanced the social status of physicians, particularly in America. (And so physicians adopted the use of scientists’ laboratory coats as a replacement for their prior striving for respectability by the use of frock coats and gold-headed canes.)

This uncritically adopted – and to physicians very congenial – conception of modern medicine as a science is now expressed, in a way, even in the most eminent of the dictionaries of medicine. Thus, according to Stedman’s [3], medicine is “the art of ... the science concerned with ...”, and in Dorland’s [4] the corresponding definition is “the art and science of ...” These definitions appear to imply that modern medicine is the union of ‘medicine the art’ and ‘medicine the science’.

This duality in the now-common conception of the essence of medicine is, however, objectionable on account of its structure. It defies the teaching in elementary logic that a logical definition posits the ‘specific difference’ of the thing in question as a species of its ‘proximate genus’ – its singular proximate genus [5]. In logical terms, therefore, medicine can be defined as a species of an art, or of a science, but not both – specifically, as a species of the art of human healthcare, or of the science of this, but not both.

If medicine is defined as (a species of) an art, then a distinction must be made between medicine and medical science (and thereby also between medicine and medical research). But if medicine is defined as (a species of) a science, then it is understood to be (quite recent in origin and) not an art (cf. art vs science, technê vs epistêmê, above).

Now, there could in principle be two separate entities called medicine, one an art, the other a science. However, this duality in the denotation of ‘medicine’ is nowhere expressly posited. But, as we noted above, the art-and-science duality in today’s definitions of medicine appears to represent the union of such a pair of very distinct denotations of ‘medicine’ – ones that have been adopted in defiance of logic [5].

Academic outlooks on medicine vis-à-vis science

In today’s medical academia, the outlook on medicine vis-à-vis science involves a salient duality, corresponding to that in medical education. There thus is, for one, the outlook of those teaching the basic sciences of medicine; and there also is, very distinct from this, the outlook of clinical academics. (Community medicine is not, generally, eminently represented in today’s medical academia.)

Contemporary teaching of the basic sciences of medicine to medical students grew, as we have described, out of its precursor in medical education à la Osler and Flexner. The philosophy underpinning this paradigmatic scientific education of future practitioners of medicine was explicitly about the essence of medicine vis-à-vis science, and it therefore merits being noted here.

In his seminal report [2], Flexner proclaimed, without any explication, that proper education in modern medicine is “dominated by knowledge that medicine is part and parcel of modern science” (p. 53; italics ours). He then sketched the practice of the “scientist” physician in comparison with that of his “empiricist” precursor (still prescientific in his mode of reasoning); and from this he – neither a physician nor a scientist, but an educator – drew the lesson that “Investigation and practice are thus one in spirit, method and object” (p. 56; italics ours). This, too, he seemingly took to be well-known and thus gave no exposition of the reasoning justifying it.

Equally unburdened by any need for explication of his rationale, Flexner treated the first half of the medical education at Johns Hopkins – especially the students’ experiences in the laboratories of the university’s hospital – as though it were a logically obvious upshot of his premise about the essence of medicine. Specifically, he believed that this education taught the students the scientific way of thinking, which to him was the essence of scientific medicine.

That rationale for the emphasis on those sciences in the Flexnerian medical education is no longer shared in the basic sciences segment of medical academia. But this has not changed the presence (eminent as ever) of the study of these sciences in medical education. Only the rationale for studying them is new.

For medical students’ extensive education in the basic sciences of medicine, the rationale now has to do with knowledge. Knowledge from these sciences is said to provide rational medicine – “practice of medicine based upon actual knowledge; opposed to empiricism” (Dorland’s). But this substitute rationale for that education also invites counterpoints.

First, knowledge from these sciences is, as we have noted above, about pathology, which addresses the objects of medicine (illnesses) rather than medicine proper. This knowledge does not therefore embody the principles of medicine definitional to normative, rational medicine.

To wit, Koch’s discovery of the somatic anomaly underlying some cases of the sickness that at the time was called ‘consumption’ (or ‘phthisis’) was a far cry from his having discovered the principles of rational medicine in respect to that illness. (Koch should have called this anomaly/illness mycobacteriosis – à la trichinosis, asbestosis, etc., but instead he redefined tuberculosis as the illness that is caused by that bacillus.)

Instead of advancing the knowledge-base of rational medicine, this discovery only added to the needs for knowledge in the practice of medicine – for diagnoses about the presence of this illness in cases of that sickness, and for prognoses concerning various aspects of the course of the sickness in actual cases of this illness (including, importantly, the way the prospects depend on the choice of treatment).

Second, empiricism of the Hippocratic type (i.e., commitment to learning medicine rationally and from experiences in the practice of it) is not antithetical to rational medicine. In fact, it has on occasion been spectacularly instructive about rational medicine. The insights of Edward Jenner and Ignaz Semmelweis are compelling examples of this. (Their insights could not have come from research in the laboratories of the basic sciences of medicine.)

And third, knowledge from the basic sciences of medicine is not the modern counterpart of medicine’s prescientific empiricism. Rather, as we pointed out above, it supplants the Hippocratic doctrine about the essence of illness.

The point here is that, from the perspective of the basic sciences of medicine — basic, as we noted, not to medicine proper but to the definition of the objects of medicine (illnesses), and for the development of new products and processes for use in it — nothing can justifiably be said about the knowledge needed in rational medicine, much less about the larger question of the sense in which, if any, modern medicine is science or scientific.

Clinical academics would ideally teach the truly requisite scientific knowledge-base of rational practice in particular disciplines of clinical medicine – derived from suitably ‘patient-oriented’ clinical research. But such has been the nature of this research – already very abundant – that this knowledge does not yet exist (for gaining scientifically knowledge-based insights into the health of patients, in terms of diagnostic probabilities, for a start).

These academics therefore continually increase their personal experience in the practice of medicine (à la Hippocratic empiricism), for one. But besides this, they now also follow ‘patient-oriented’ clinical research — the publicly documented experiences in it.

This outlook on clinical research in relation to clinical practice has, in recent decades, been explicit in the ideology of the ‘evidence-based medicine’ (EBM) movement [6] – an ideology which originated in clinical academia and is now widely embraced in it (though commonly without familiarity with its expressly codified tenets, let alone learned-and-critical thought about these).

This movement’s original ideologues (Sackett et alii) introduced “clinical epidemiology” as “a basic science for clinical medicine” [7]. Its precepts were intended to provide for practising clinicians a critical understanding of published research on topics relevant to their respective disciplines of clinical medicine. The research that is followed in the practice of EBM bears no relation to the sciences that are addressed in medical education. The research at issue here is ‘statistico-medical’ rather than bio-medical.

The most fundamental tenet of the EBM movement is that each clinician is to personally follow reports of studies potentially relevant to his/her practice, to critically consider the evidence in each of these, and then to apply his/her own judgement about the burden of the evidence (as ersatz knowledge) to their care of patients [8].

Practice of EBM is thus not knowledge-based, or even objectively evidence-based. Its basis is, ultimately, subjectivistic. The practices of EBM are, ultimately, opinion-based. Besides, the teachings in clinical epidemiology are, in important ways, untenable. (More on this below.)

This EBM culture of today’s clinical academics clearly indicates that they do not view modern clinical medicine as purely art and, thus, as wholly distinct from science. And more to this effect is that they expect their ‘trainees’ to actually conduct research in preparation for clinical practice. This fact (odd though it is) reinforces the point that clinical academics see the modern practice of clinical medicine as having an active scientific dimension (even beyond that which is inherent in EBM). Nevertheless, they don’t think of (the practice of) modern clinical medicine as science, but as ‘clinical epidemiology’ and, hence, as research-informed art.

The denotation of ‘medical’ in the science-related phrases above requires clarification. Use of the term ‘medical research’ – or its cognate ‘medical science’ – does not inherently imply viewing medicine as a science. The intended meaning can be that of medicine-serving research, or science, extrinsic to medicine proper.

Publishing reports on medical research in medical journals also does not inherently mean that the editors think of medicine as a science. The reason for this routine can (furtively) be the wish to bolster the lay conception of medicine as science, as this public image of medicine enhances the status and authority of physicians and cultivates among societal authorities the belief that matters medical are beyond lay understanding, and that medical professions therefore deserve autonomy (in the framework of a ‘social contract’ to this effect). (This motive may also underlie the emphasis on medical science in the education of physicians.)

Our own outlook on medicine vis-à-vis science

While it is now, as we’ve outlined here, quite commonplace to hold that the originally pure art of medicine has recently been supplanted, at least in part, by medicine as a science, we do not share this view (which has not been affirmed in the public discourse of relevant scholars).

In our considered view, all of medicine still is, and always will be, purely art (and thus not an amalgam of art and science, let alone purely science). And accordingly, it also is our firm view that all of medical research is extrinsic to medicine proper – that this research is medicine-serving without being (an aspect of) medicine.

The biological research by Pasteur and Koch alluded to above was, as we noted, conducted as work of science in laboratories of science, and thus not as work of medicine in practices of medicine. It exemplifies research in the basic sciences of medicine in both of the two senses in which these sciences can serve the advancement of medicine: those sciences can be ‘basic’ to development – technological – of new products and processes for use in the arts of medicine, and to definition (and elaboration) of illnesses (as somatic anomalies).

Research in the basic sciences of medicine is health research in the narrow, absence-of-illness meaning of ‘health’ when addressing the normal structures and functions of the human body. But in the common, broader meaning of ‘health’, it subsumes research on pathological entities of the soma (representing species of ill health/illness). This research is only contingently medical. It actually is medical only if it is ‘applied’ in the sense of being intended to serve medicine, and even when this is the case, this research rarely leads to innovation in medicine.

This research, as we’ve argued above, is not the source of the knowledge-base of the practice of rational medicine.

Another, very different, major branch of medical research – also extrinsic to medicine proper – is research for the advancement of the actual knowledge-base of medicine proper [9].

Evidence from this research is, as we noted above, the existing scientific addendum to the Hippocratic basis for learning medicine. While it is science in the research meaning of ‘science,’ it is not intrinsic to any science. There is no science whose body of knowledge amounts to the requisite knowledge-base of an art (of medicine or anything else). This is inherently medical research: all of these studies are supposed to contribute to the evidence-base of the knowledge-base of the practices of medicine. This research is, in this sense, quintessentially applied medical research [9].

Now, even though an enormous amount of research, derivative as well as original, of this latter type (statistico-medical rather than bio-medical) has already been published (in medical journals), contemporary clinical practices are still only opinions-based, rather than (scientifically) knowledge-based. Even the so-called evidence-based medicine is, as we have noted, no exception to this. (Seeking ‘second opinions’ is natural in opinion-based medicine, but not in knowledge-based medicine.)

The root reason for this – quite unsatisfactory – state of affairs is, we hold, that the objects of ‘patient-oriented’ research have not been sufficiently patient-relevant, and therefore it has not been possible to translate the evidence from this research into the required knowledge. This problem persists in the ‘clinical epidemiology’ precepts about ‘patient-oriented’ clinical research.

We thus see a need for major transformations in the theoretical framework of this quintessentially applied clinical research, in two stages [10]. First, there is, the need (ontal) to adopt a tenable conception of the nature (form) of the requisite knowledge-base of medicine. Then, subordinate to this, there is the (epistemic) need to adopt a theoretical framework for the research proper such that it actually produces the requisite evidence-base for knowledge of the type which truly is needed.

Specifically, the requisite knowledge-base of clinical medicine must be understood to be of the form of gnostic – dia-, aetio-, and prognostic – probability functions for suitably defined domains of case presentation for gnosis; and quintessentially applied clinical research – gnostic research – needs to produce valid empirical content in these forms. Furthermore, for each well-designed GPF (gnostic probability function), the results of all valid studies on it must be (synthesised and) translated into a GPF representing knowledge about the magnitudes of the parameters involved — according to the consensus judgment of (representatives of) the relevant scientific community.

From the perspective of this (quintessentially applied) medical research, any textbook of modern medicine – naturally specific to a particular medical discipline – would not be organised by any taxonomy of illnesses (à la Osler), but by the types of case presentation that are of concern (for gnoses, first off).

Resolving the art vs science dilemma in medicine

As a summary of sorts of what we’ve said about medicine in all the foregoing, figure 1 depicts the ever-growing and also otherwise ever-changing ‘Tree of medicine’, with special reference to scholarly influences on it, from Greek antiquity to the present and beyond. Apart from the original, fundamental influence of Hellenic philosophy, of particular note about this tree in the present context are the two types of research that, while extrinsic to it, have been very important to its evolution. These are the ‘basic-applied’ and ‘quintessentially applied’ lines of medical research. They influence, respectively, the roots and the branches of the tree.

An added scholarly influence now is that of critical theory of medicine and medical research. The concerns in this theoretical discipline have, as illustrated by this essay, included critical inquiry into the tree’s evolution up to the present. Its focus now is on charting the future of these two, closely interrelated scholarly fields (medicine and medical research). Recently, the formulation of the theoretical framework of ‘meta-epidemiological clinical research’ for the development of the requisite knowledge base of scientific clinical medicine (in terms of gnostic probability functions) has been a major element of these futuristic concerns [10].

As for progress in medicine, the big picture from today’s perspective is this. While the temple medicine of ancient Greece was supplanted by empirico-rational Hippocratic medicine, and the advent of medical science brought major progress, but nevertheless left modern medicine essentially opinions-based, a radical transformation in modern medicine is now needed. This is the replacement of the prevailing opinions-based medicine with scientifically knowledge-based medicine – by scientific medicine in this meaning of the term (very different from Flexner’s) – within a rational theoretical framework.

Fundamental to this now-topical major mission is, naturally, a tenable conception of the in-principle essence of modern medicine, with special reference to the sense, if any, in which it is science. But, as we have here explained, there still is, even in medical academia, considerable confusion about this.

We therefore feel the need, now, for learned and thoughtful public discourse aimed at resolving once and for all the core question addressed in the foregoing, namely: has the ancient art of medicine recently become a science in addition to still being an art, or, even, in lieu of this age-old essence of medicine? And closely related to this are the questions about the tenable conception of the essence of medical science and that of scientific medicine, which we’ve also here addressed, to some extent.

Such discourse we expect to converge to common recognition, in medical academia, of modern medicine as the aggregate of its constituent differentiated arts, and of each of them still being in seriously unmet need of a scientific knowledge-base from research extrinsic to the art – within a tenable theoretical framework.

Figure 1: Evolution of (the tree of) medicine, from the time of Hippocrates to the present and beyond, with special reference to scholarly influences (in red boxes): In Greek antiquity, philosophy brought empiricism to replace mythology as the basis of medicine, but the result was actually another form of doctrine-based medicine, DBM. Starting in the late nineteenth century, ‘bio-medical’ science has produced knowledge, providing for the development of novel products and processes for use in medicine. From the mid-twentieth century onwards, epidemiological research of the statistical type has provided for community medicine’s transition from DBM (preventive) to its knowledge-based counterpart, KBM. The advent of statistical research for clinical medicine followed, and this became the signature concern of ‘clinical epidemiologists’, with a view to the practice of evidence-based medicine (EBM) by clinicians. Most recently, critical theory of medicine and medical research has addressed (critically) the joint evolution of these fields, and has also charted the – ‘meta-epidemiological’ – clinical research that is needed to provide advancement from today’s EBM to the KBM of tomorrow.

 

Implications of our outlook on medicine vis-à-vis science

We expect recognition of our outlook on the essence of medicine to have major implications in terms of needed reforms in medical academia and, thereby, in medicine proper.

First, we expect it to become appreciated that educating undifferentiated physicians à la Osler and Flexner is no longer called for or even practicable. The graduates of that education are now merely ‘physicians’ unqualified to practise any of the disciplines of contemporary (or future) medicine. That ‘generalist’ education therefore needs to be replaced by education and training (E&T) that is, from its very beginning, preparatory to practice in a particular one of the constituent disciplines of medicine, in two stages.

The first stage would, just as at present, be shared across all the various disciplines of modern medicine. It would be reformed, however, to focus on those educational needs that truly are common across all these arts. It would focus on what in this sense truly is ‘the medical common.’ Very notably, knowledge from the bio-medical sciences is not part of this (as it does not have applications in vitreoretinal ophthalmology, HIV epidemiology and, also, in each of the other disciplines of modern medicine). Similarly, introduction to whatever subset of the disciplines of contemporary medicine does not belong in a well-construed ‘medical common.’

For these first-stage studies to be suitably propaedeutic to the E&T specific to whichever particular discipline of medicine, the very first topic would be the essence of modern medicine – as no longer an art, nor in any sense a science, but as the aggregate of its constituent arts, each of them distinguished from the corresponding para-medical disciplines (nursing, among others) by the central role of first-hand gnoses in medicine.

The second, main stage would, naturally, be discipline-specific. For any given student it needs to focus, ab initio (rather than with stage-wise increasing specificity), on the knowledge and skills that are needed in the fully competent practice of the particular art of medicine the student is preparing for.

For any given clinical discipline, this teaching needs to be redesigned to address, first, the spectrum of case presentations in it; then, the profile-conditional gnostic probabilities; and finally, the current state of knowledge about the magnitudes of these probabilities. (The genesis of that knowledge is not relevant to the teaching.)

This reformation of the core function (education) of medical academia naturally means leaving education in the biomedical sciences for other segments of academia to provide (including technological academia) – as preparation for careers in these (rather than in the arts of modern medicine). It also means that a student begins the education and training specific to his/her particular discipline of medicine much earlier – right after their education in ‘the medical common’ (paired down to what truly belongs therein).

The research of the teachers of the various arts of modern medicine needs to conform to the core idea – enormously productive – behind the establishment of the first research-based university (U Berlin, in 1810). In these terms, the research of the teachers has advancement of the contents of their own teaching as its raison d’être. With the knowledge-base of a particular discipline of clinical medicine the generic object of a medical academic’s teaching, his/her research needs to be of the form of the suitably-transformed gnostic clinical research.

For that quintessentially-applied (gnostic) clinical research to expeditiously provide for transformation of today’s still largely prescientific clinical medicine into its generally scientific successor, needed is a globally coordinated programme of that research [10]; and also needed is a programme of continually updated translations of the thus-accrued evidence into the requisite scientific knowledge-base of clinical medicine – imbedded in cyberspace and guiding, from there, the practices of clinical medicine through scientific ‘expert systems.’

Financial disclosure

The Helmut Horten Foundation provided financial support through its funding of the Horten Centre for Patient-Oriented Research and Knowledge Transfer.

Potential competing interests

No conflict of interest relevant to this article was reported.

 

Johann Steurer: Horten Centre for Patient-Oriented Research and Knowledge Transfer, University of Zurich, Pestalozzistrasse 24, CH-8032 Zürich

 

References

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