Originally published on July 25, 201

This is the 28th article in the Profiles in Knowledge series featuring thought leaders in knowledge management. It is also the tenth of these about key contributors who are gone but not forgotten. And it is my 201st LinkedIn article and 402nd blog post since I started blogging in 2006.

Given that this is the start of my next hundred articles, I thought it would be a good time to reflect on some important philosophy about knowledge. This article focuses on philosophers and scientists who espoused sometimes controversial ideas about knowledge and science. They did not write specifically about knowledge management, but their work has been influential in the writing and thinking of many KM thought leaders — and of each other. Here are quotes from each one.

1. Michael Polanyi (1891–1976)


  1. One of the most novel philosophers of sciences in the 20th century was the physical chemist Michael Polanyi. His first group of philosophical essays appeared in 1946 under the title Science, Faith and Society, followed by Personal Knowledge: Towards a Post-Critical Philosophy, The Tacit Dimension, and other volumes.
  2. One of his notable philosophical interventions occurred at a conference in Oxford in 1961, where Thomas S. Kuhn summarized his thesis on paradigms, normal science, and scientific revolutions which would be published as The Structure of Scientific Revolutions. Polanyi followed up Kuhn’s presentation with the comment that he had been trying to call attention to the very view that Kuhn now was arguing, which is a view undercutting philosophical preoccupation with logical positivism and falsification. Scientists, Polanyi argued, are not heretics driven by skepticism, but rather are steadfastly committed to established beliefs and dogmas within the scientific community. It is the social scientific community, not a rational scientific method, that is the determining condition of scientific knowledge.
  3. Polanyi’s philosophy of scientific practice and tacit knowledge has influenced historians and sociologists of science, more than philosophers of science, perhaps because of the difficulty of following Polanyi’s attempt to define scientific knowledge as personal knowledge while avoiding its characterization as subjective knowledge. For Polanyi, science remains objective, not in the detachment of the knower from the known, but in the power of science to establish contact with a hidden reality based in the skills and commitment of the knower.
  1. Polanyi’s work as a scientist made significant contributions in the area of physical chemistry. Based on his experiences as a natural scientist, Polanyi turned his attention to the philosophy of science. He argued against dominant theories of positivism and explicated the importance of understanding “tacit knowledge,” unspoken knowledge that underlies scientific theories. While the dominant philosophers of science focused on logic and linguistic analyses of scientific theories, Polanyi highlighted the role of pre-linguistic, implicit understanding (“tacit knowledge”) in developing scientific theories. His notion of “tacit knowledge” was a precursor to the idea of paradigm by Thomas Kuhn and ideas held by subsequent philosophers of science, such as Feyerabend. Also, Polanyi’s concept of “tacit knowledge” is an important thought for the development of knowledge management.
  2. Tacit knowledge is not easily shared. One of Polanyi’s famous aphorisms states: “We know more than we can tell.” Tacit knowledge consists often of innate habits and culture that are not easily recognized. In knowledge management, tacit knowledge refers to knowledge which is only known by an individual and is difficult to communicate to the rest of an organization. Knowledge that can be communicated more easily is called explicit knowledge. The process of transforming tacit knowledge into explicit knowledge is known as codification or articulation.
  3. Polanyi argued that knowing always had an indispensable personal component. With this he critiqued the objectivist position of which he was deeply concerned about a lack of ethical commitment or considerations. Building on general ideas from Gestalt-psychology he described a difference between two kinds of awareness: Subsidiary and focal awareness. In focal awareness, one is aware of a coherent whole, a Gestalt. In subsidiary awareness, one is implicitly conscious of the different impressions, memories that build this Gestalt. This Gestalt is not given, but it is an achievement, realized by interpretative skills. The whole notion of explicit knowledge as something that could be captured in an information system is at odds with this interplay between subsidiary and focal awareness. The tacit can be known but only in terms of the Gestalt that it bears on. The explicit is gone in the next moment, when a new Gestalt is formed in the focal awareness.


  1. Into every act of knowing there enters a passionate contribution of the person knowing what is being known and that this coefficient is no mere imperfection but a vital component of his knowledge.
  2. While tacit knowledge can be possessed by itself, explicit knowledge must rely on being tacitly understood and applied. Hence all knowledge is either tacit or rooted in tacit knowledge. A wholly explicit knowledge is unthinkable.
  3. We know more than we can tell.
  1. Central to Polanyi’s thinking was the belief that creative acts (especially acts of discovery) are shot-through or charged with strong personal feelings and commitments (hence the title of his most famous work Personal Knowledge). Arguing against the then dominant position that science was somehow value-free, he sought to bring into creative tension a concern with reasoned and critical interrogation with other, more “tacit,” forms of knowing.
  2. Polanyi’s argument was that the informed guesses, hunches and imaginings that are part of exploratory acts are motivated by what he describes as “passions.” They might well be aimed at discovering “truth,” but they are not necessarily in a form that can be stated in propositional or formal terms. As he wrote in The Tacit Dimension, we should start from the fact that “we can know more than we can tell.” He termed this pre-logical phase of knowing as “tacit knowledge.” Tacit knowledge comprises a range of conceptual and sensory information and images that can be brought to bear in an attempt to make sense of something. Many bits of tacit knowledge can be brought together to help form a new model or theory. This inevitably led him to explore connoisseurship and the process of discovery (rather than with the validation or refutation of theories and models — in contrast with Popper, for example).

Audio Files

  1. The Destruction of Reality
  2. The Realm of the Unspoken
  3. The Vindication of Reality
  4. A Society of Explorers


2. Sir Karl Popper (1902–1994)


  1. Karl Popper was one of the most influential philosophers of science of the 20th century. He made significant contributions to debates concerning general scientific methodology and theory choice, the demarcation of science from non-science, the nature of probability and quantum mechanics, and the methodology of the social sciences. His work is notable for its wide influence both within the philosophy of science, within science itself, and within a broader social context.
  2. He holds that scientific practice is characterized by its continual effort to test theories against experience and make revisions based on the outcomes of these tests. By contrast, theories that are permanently immunized from falsification by the introduction of untestable ad hoc hypotheses can no longer be classified as scientific. Among other things, Popper argues that his falsificationist proposal allows for a solution of the problem of induction, since inductive reasoning plays no role in his account of theory choice.
  3. With respect to the social sciences, Popper argued against the historicist attempt to formulate universal laws covering the whole of human history and instead argued in favor of methodological individualism and situational logic.
  1. Karl Popper is generally regarded as one of the greatest philosophers of science of the 20th century. He was also a social and political philosopher of considerable stature, a self-professed critical-rationalist, a dedicated opponent of all forms of skepticism, conventionalism, and relativism in science and in human affairs generally and a committed advocate and staunch defender of the “Open Society.” One of the many remarkable features of Popper’s thought is the scope of his intellectual influence: he was lauded by Bertrand Russell, taught Imre Lakatos, Paul Feyerabend and the future billionaire investor and philanthropist George Soros at the London School of Economics, numbered David Miller, Joseph Agassi, Alan Musgrave and Jeremy Shearmur amongst his research assistants there and had reciprocally beneficial friendships with the economist Friedrich Hayek and the art historian Ernst Gombrich. Additionally, Peter Medawar, John Eccles and Hermann Bondi are amongst the distinguished scientists who have acknowledged their intellectual indebtedness to his work, the latter declaring that “There is no more to science than its method, and there is no more to its method than Popper has said.”
  2. For Popper, the growth of human knowledge proceeds from our problems and from our attempts to solve them. These attempts involve the formulation of theories which, if they are to explain anomalies which exist with respect to earlier theories, must go beyond existing knowledge and therefore require a leap of the imagination. For this reason, Popper places special emphasis on the role played by the independent creative imagination in the formulation of theory. The centrality and priority of problems in Popper’s account of science is paramount, and it is this which leads him to characterize scientists as “problem-solvers.” Further, since the scientist begins with problems rather than with observations or “bare facts,” Popper argues that the only logical technique which is an integral part of scientific method is that of the deductive testing of theories which are not themselves the product of any logical operation. In this deductive procedure conclusions are inferred from a tentative hypothesis. These conclusions are then compared with one another and with other relevant statements to determine whether they falsify or corroborate the hypothesis. Such conclusions are not directly compared with the facts, Popper stresses, simply because there are no “pure” facts available; all observation-statements are theory-laden, and are as much a function of purely subjective factors (interests, expectations, wishes, etc.) as they are a function of what is objectively real.


  1. Popper’s Demarcation Between Science and Metaphysics
  2. Popper’s Philosophy of Science



3. Bernard Lonergan (1904–1984)


His opus covers methodological issues in the natural sciences, the human sciences, historical scholarship, aesthetics, economics, philosophy and theology. He begins with an invitation to consider in ourselves what occurs when we come to knowledge. He then defines a corresponding epistemological meaning of objectivity. From there he lays out basic metaphysical categories applicable in the sciences. Finally, he proposes a methodical framework for collaboration in resolving basic differences in all these disciplines.

In Insight and Method in Theology, Lonergan leads readers to discover what happens when they reach knowledge, evaluate options, and make decisions. He expects that those who make these discoveries about themselves reach an explicit knowledge of how anyone reaches knowledge and values, how inquiries are guided by internal criteria, and how therefore any inquiry may be called “objective.” Such objectivity implies structural parallels between the processes of inquiry and the structures of what any inquirer, in any place or time, can know and value. Lonergan proposes that these structures, in turn, provide a personally verified clarification of the methods specific to the natural and human sciences, historiography and hermeneutics, economics, aesthetics, theology, ethics, and philosophy itself.

So there are four questions for anyone seeking to ground the methods of any discipline.

  1. A cognitional theory asks, “What do I do when I know?” It encompasses what occurs in our judgments of fact and value.
  2. An epistemology asks, “Why is doing that knowing?” It demonstrates how these occurrences may appropriately be called “objective.”
  3. A metaphysics asks “What do I know when I do it?” It identifies corresponding structures of the realities we know and value.
  4. A methodology asks, “What therefore should we do?” It lays out a framework for collaboration, based on the answers to the first three questions.

Bernard Lonergan is regarded by many as one of the greatest philosophical minds of the twentieth century. He is the author of Insight: A Study of Human Understanding in which he worked out what he called a Generalized Empirical Method. Here are two highlights.

What am I doing when I am knowing?

The first eleven chapters of Lonergan’s book Insight — his monumental work — are an attempt to answer this question. Why did he ask this question? There are at least two reasons:

  1. to provide what he called a “common ground” on which people could meet one another, that is, the common ground of the operations through which they pursue meaning and truth, and
  2. to provide what is probably a solution to the fragmentation of knowledge — not by attempting to integrate the content of knowledge, which is not possible, but by acknowledging the same operations of experiencing, understanding, and judging in all fields. This acknowledgment, which Lonergan’s book Insight shows, brings a startling unity to knowledge and to the pursuit of understanding in every field. It helps us relate such ‘hard sciences’ as mathematics, physics, and chemistry to the sciences of life, and to relate all of these to psychology, philosophy, the arts, and theology.

The key is the act of insight. Lonergan is seeking an insight into insight itself. He writes: “…to grasp it in its conditions, its working, and its results is to confer a basic yet startling unity on the whole field of human inquiry and human opinion.”

What difference does this make?

From the study of insight, Lonergan tackles some of the major challenges of our time, all of which are in one way or another a function of biases that interfere with the operations of experiencing, understanding, and judging. So not only does he show us many different kinds of insights; he also displays several kinds of bias that interfere with insight and prevent us from being attentive, intelligent, reasonable, and responsible. There is the psychic bias that comes from trauma, the individual bias of the egoist, the group bias of the privileged classes, and a general bias that we all have against asking the hard questions and facing the ultimate issues and long-range consequences of our actions. All of these are spelled out in intricate detail in his work.



4. Imre Lakatos (1922–1974)


Lakatos was at first a close follower and defender of Karl Popper and Popperian falsificationism, but eventually he and Popper broke with each other, so much so that Popper denounced Lakatos somewhat bitterly and claimed that Lakatos misunderstood and misrepresented him (in The Philosophy of Karl Popper), and Lakatos — along with his friend and colleague Paul Feyerabend, another lapsed Popperian — came to minimize the importance of Popper and Popper’s work.

The group of Popper students and former students has sometimes been called, somewhat derisively, the “Popper Church.” Popper taught his students to have a critical stance, but he seems to have been unable to tolerate criticism from his students and former students. The late W.W. Bartley, III, another Popperian and editor of some of Popper’s works, remained faithful to Popper until Popper’s death, and wrote some harsh things against Lakatos. Walter B. Weimer wrote that the contentiousness within the Popper Church was “a lightly disguised squabble of alley cats” (From Notes on the Methodology of Scientific Research).

Feyerabend, another former Popperian who later joined with Lakatos in mocking Popper and denigrating his importance, wrote that “Popper is not a philosopher, he is a schoolmaster…” suggesting that he thought of Popper as a closed-minded pontificator who was unpleasant and didactic in his procedures instead of exhibiting the open, critical, and inquiring attitude that his own philosophy recommended.

No doubt Popper also became jealous of the acclaim and attention that LSE students gave to Lakatos, an acclaim and attention that has only grown in the intervening years since his death. Moreover, Popper likely thought that Lakatos would have been little as a philosopher without what he had received from Popper and that he shamelessly took much from Popper and represented this work as his own.

Imre Lakatos has two chief claims to fame.

  1. The first is his Philosophy of Mathematics, especially as set forth in “Proofs and Refutations” (1963–64) a series of four articles, based on his PhD thesis, and written in the form of a many-sided dialogue. These were subsequently combined in a posthumous book and published, with additions, in 1976. The title is an allusion to a famous paper of Popper’s, “Conjectures and Refutations” (the signature essay of his best-known collection), in which Popper outlines his philosophy of science. Lakatos’s point is that the development of mathematics is much more like the development of science as portrayed by Popper than is commonly supposed, and indeed much more like the development of science as portrayed by Popper than Popper himself supposed.
  2. Lakatos’s second major contribution to philosophy, his “Methodology of Scientific Research Programmes” or MSRP (developed in detail in in his FMSRP), a radical revision of Popper’s Demarcation Criterion between science and non-science, leading to a novel theory of scientific rationality. This is arguably a lot more realistic than the Popperian theory it was designed to supplant (or, in earlier formulations, the Popperian theory that it was designed to amend). For Popper, a theory is only scientific if is empirically falsifiable, that is if it is possible to specify observation statements which would prove it wrong. A theory is good science, the sort of theory you should stick with (though not the sort of thing you should believe as Popper did not believe in belief), if it is refutable, risky, and problem-solving and has stood up to successive attempts at refutation. It must be highly falsifiable, well-tested but (thus far) unfalsified.

The best-known of Lakatos’s “Conference Proceedings” is Criticism and the Growth of Knowledge, which became an international best-seller. It contains Lakatos’s important paper “Falsification and the Methodology of Scientific Research Programmes” (FMSRP), in which Lakatos distinguished dogmatic, naïve and sophisticated falsificationist positions, attributing them to “Popper 0, Popper 1 and Popper 2” — or as he otherwise put it, “proto-Popper, pseudo-Popper and proper-Popper.” (Popper did not appreciate being disassembled into temporal or ideological parts and protested “I am not a Trinity.”)

Lakatos’s methodology has been seen, rightly, as an attempt to reconcile Popper’s falsificationism with the views of Thomas Kuhn. Popper saw science as consisting of bold explanatory conjectures, and dramatic refutations that led to new conjectures. Kuhn (and Polanyi before him) objected that

No process yet disclosed by the historical study of scientific development at all resembles the methodological stereotype of falsification by direct comparison with nature. (Kuhn 1962: 77)

Instead, science consists of long periods of “normal science”, paradigm-based research, where the task is to force nature to fit the paradigm. When nature refuses to comply, this is not seen as a refutation, but rather as an anomaly. It casts doubt, not on the ruling paradigm, but on the ingenuity of the scientists — “only the practitioner is blamed, not his tools”. It is only in extraordinary periods of “revolutionary science” that anything like Popperian refutations occur.

Lakatos proposed a middle-way, in which Kuhn’s socio-psychological tools were replaced by logico-methodological ones. The basic unit of appraisal is not the isolated testable theory, but rather the “research programme” within which a series of testable theories is generated. Each theory produced within a research programme contains the same common or “hard core” assumptions, surrounded by a “protective belt” of auxiliary hypotheses. When a particular theory is refuted, adherents of a programme do not pin the blame on their hard-core assumptions, which they render “irrefutable by fiat”. Instead, criticism is directed at the hypotheses in the “protective belt” and they are modified to deal with the problem. Importantly, these modifications are not random — they are in the best cases guided by the heuristic principles implicit in the “hard core” of the programme. A programme progresses theoretically if the new theory solves the anomaly faced by the old and is independently testable, making new predictions. A programme progresses empirically if at least one of these new predictions is confirmed.

Notice that a programme can make progress, both theoretically and empirically, even though every theory produced within it is refuted. A programme degenerates if its successive theories are not theoretically progressive (because it predicts no novel facts), or not empirically progressive (because novel predictions get refuted). Furthermore, and contrary to Kuhn’s idea that normally science is dominated by a single paradigm, Lakatos claimed that the history of science typically consists of competing research programmes. A scientific revolution occurs when a degenerating programme is superseded by a progressive one. It acquires hegemonic status though its rivals may persist as minority reports.

Kuhn saw all this as vindicating his own view, albeit with different terminology (Kuhn 1970: 256, 1977: 1). But this missed the significance of replacing Kuhn’s socio-psychological descriptions with logico-methodological ones. It also missed Lakatos’s claim that there are always competing programmes or paradigms. Hegemony is seldom as total as Kuhn seems to suggest.




5. Thomas Kuhn (1922–1996)


Thomas Samuel Kuhn is one of the most influential philosophers of science of the twentieth century, perhaps the most influential. His 1962 book The Structure of Scientific Revolutions is one of the most cited academic books of all time. Kuhn’s contribution to the philosophy of science marked not only a break with several key positivist doctrines, but also inaugurated a new style of philosophy of science that brought it closer to the history of science. His account of the development of science held that science enjoys periods of stable growth punctuated by revisionary revolutions. To this thesis, Kuhn added the controversial “incommensurability thesis,” that theories from differing periods suffer from certain deep kinds of failure of comparability.

A particularly important part of Kuhn’s thesis in The Structure of Scientific Revolutions focuses upon one specific component of the disciplinary matrix. This is the consensus on exemplary instances of scientific research. These exemplars of good science are what Kuhn refers to when he uses the term “paradigm” in a narrower sense. He cites Aristotle’s analysis of motion, Ptolemy’s computations of plantery positions, Lavoisier’s application of the balance, and Maxwell’s mathematization of the electromagnetic field as paradigms. Exemplary instances of science are typically to be found in books and papers, and so Kuhn often also describes great texts as paradigms — Ptolemy’s Almagest, Lavoisier’s Traité élémentaire de chimie, and Newton’s Principia Mathematica and Opticks. Such texts contain not only the key theories and laws, but also — and this is what makes them paradigms — the applications of those theories in the solution of important problems, along with the new experimental or mathematical techniques (such as the chemical balance in Traité élémentaire de chimie and the calculus in Principia Mathematica) employed in those applications.

Kuhn’s work met with a largely critical reception among philosophers. Some of this criticism became muted as Kuhn’s work became better understood and as his own thinking underwent transformation. At the same time other developments in philosophy opened up new avenues for criticism. That criticism has largely focused on two areas. First, it has been argued that Kuhn’s account of the development of science is not entirely accurate. Secondly, critics have attacked Kuhn’s notion of incommensurability, arguing that either it does not exist or, if it does exist, it is not a significant problem. Despite this criticism, Kuhn’s work has been hugely influential, both within philosophy and outside it. The Structure of Scientific Revolutions was an important stimulus to what has since become known as “Science Studies,” in particular the Sociology of Scientific Knowledge (SSK).

  1. For Kuhn, scientific revolutions involved paradigm shifts that punctuated periods of stasis or normal science. Towards the end of his career, however, Kuhn underwent a paradigm shift of his own — from a historical philosophy of science to an evolutionary one.
  2. The paradigm concept loomed large in Kuhn’s new image of science. He defined the concept in terms of the community’s concrete achievements, such as Newtonian mechanics, which the professional can commonly recognize but cannot fully describe or explain. A paradigm is certainly not just a set of rules or algorithms by which scientists blindly practice their trade. In fact, there is no easy way to abstract a paradigm’s essence or to define its features exhaustively. Moreover, a paradigm defines a family resemblance, à la Wittgenstein, of problems and procedures for solving problems that are part of a single research tradition.
  3. Although scientists rely, at times, on rules to guide research, these rules do not precede paradigms. Importantly, Kuhn was not claiming that rules are unnecessary for guiding research but rather that they are not always sufficient, either pedagogically or professionally. Kuhn compared the paradigm concept to Polanyi’s notion of tacit knowledge, in which knowledge production depends on the investigator’s acquisition of skills that do not reduce to methodological rules and protocols.


  1. Profile: Reluctant Revolutionary
  2. What Thomas Kuhn Really Thought about Scientific “Truth
  • James D. Strauss
  1. Thomas Kuhn’s Concept Of Paradigm
  2. Crisis Narrative and Science
  3. Thomas Kuhn’s Science as a System of Traditional Authority
  4. Towards Understanding Thomas Kuhn



Comparisons and Compilations


  • James D. Strauss
  1. The Heart of Post Modernism is “Rooted” In Thomas Kuhn, Karl Popper, Kurt Goedel’s Theorem and Michael Polanyi’s Debate Concerning Narrative Displacement
  2. Prolegomena to Theories of Scientific Revolution (Kant, Popper, Lakatos, et al.)
  1. Part 1: a rejection of empiricism
  2. Part 2: the virtue of refutation
  3. Part 3: rejecting politics as science
  4. Part 4: Lakatos, Kuhn and Feyerabend
  5. Part 5: the craving to be right
  1. Karl Popper on Scientific Method and Knowledge
  2. Michael Polanyi on Scientific Method and Knowledge
  3. A Comparison of Whitehead’s and Lonergan’s Interpretations of Empirical Scientific Method to those of Karl Popper and Michael Polanyi
  1. In a 1987 essay in Nature, “Where Science Has Gone Wrong,” two British physicists fretted over the public’s growing antipathy toward science. They blamed this trend on philosophers who deny that science discovers objective, absolute truths. The essay featured photographs of three “betrayers of the truth”: Karl Popper, Thomas Kuhn and Paul Feyerabend.
  2. All philosophical skeptics are vulnerable to self-contradiction. Popper and Kuhn both fell into this trap in their interviews with me. Popper, who railed against certainty in science and politics, pounded the table and insisted that he was not dogmatic. Kuhn twisted himself in knots trying to explain precisely what he meant when he talked about the impossibility of true, objective communication.
  1. But if observations are theory-laden, this means that observations are simply theories, and then how can one theory falsify (never mind verify) another theory? Curiously, the full implications of this little complication ‘were not fully grasped by Popper, but by Imre Lakatos; not only are scientific theories not verifiable, they are not falsifiable either — “If a theory is refuted. it is not necessarily false”
  2. Kuhn’s view, that a proposition is scientific if it is sanctioned by the scientific establishment, gives rise to the problematic question: what exactly makes an establishment “scientific”? This particular Gordian knot was cut by Paul Feyerabend: any proposition is scientific — “There is only one principle that can be defended under all circumstances and in all stages of human development. It is the principle: Anything goes”
  3. For reasons known only to themselves, the advocates of the antitheses refuse to recognize that their ideas are flagrantly self-refuting — they negate and destroy themselves. And if a statement entails its own falsity, then it must be nonsense: the proposition “there is no truth” contradicts itself, and hence some truths must exist after all. Similarly, the stricture “nothing is certain, everything is doubtful”’ casts doubt, besides everything else, upon itself, and so some certain and undoubted things must exist. Likewise, if “anything goes”, then “nothing goes” must go too.
  4. To most people this is sufficient refutation of the antitheses. But instead the skeptics and nihilists persist with doubting anything and everything with a cocksureness that beats any avowed dogmatist — they are dogmatic skeptics, and they would question anything except their own doubts. In the same vein, the epistemological relativists, who uphold the complete equivalence of all “paradigms,” may be aptly termed absolute relativists.
  5. In any event, the spectacle of the supporters of the antitheses appealing to the very standards which they are bent on attacking is reassuring to those who uphold these standards. For example, those who claim to have refuted inductive reasoning have done so by employing inductive reasoning itself, as follows: from the true fact that many examples of inductive inference have indeed been shown to be invalid, these people inferred (inductively!) that all examples of inductive inference will be shown to be invalid.


Knowledge Management Author and Speaker, Founder of SIKM Leaders Community, Community Evangelist, Knowledge Manager https://sites.google.com/site/stangarfield/

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