• March 2011 – Three Dimensions of Expertise
  • January 2010 – Third Wave criminology: Guns, crime and social order
  • November 2008 – Counterfeit Scientific Controversies Working Paper; Talking Treatments Working Paper
  • July 2008 – Hawk-Eye paper
  • December 2007
  • August 2007 – Rethinking Expertise
  • March 2007
  • December 2006
  • August 2006
  • July 2006
  • 2004
  • 2002
  • Alternative Approaches
  • Publications on Tacit Knowledge


March 2011

Three Dimensions of Expertise

Harry Collins

Cardiff University

Abstract: Psychologists and Philosophers tend to treat expertise as a property of special individuals. These are individuals who have devoted much more time than the general population to the acquisition of their specific expertises. They are often said to pass through stages as they move toward becoming experts, for example, passing from an early stage, in which they follow self-conscious rules, to an expert stage in which skills are executed unconsciously. This approach is ‘one-dimensional’. Here two extra dimensions are added. They are drawn from the program known as Studies of Expertise and Experience (SEE) and its ‘Periodic Table of Expertises’. SEE, which is sociological, and/or Wittgensteinian, in inspiration, takes expertise to be the property of groups; there are ‘domains’ of expertise. Under SEE, level of expertise grows with embedding in the society of domain experts; the key is the transmission of domain-specific tacit knowledge. Thus one extra dimension is degree of exposure to tacit knowledge. Under SEE domains can be big or small so there can be ‘ubiquitous tacit knowledge’, such as natural language speaking or other elements of general social behaviour, which belong to every member of a society. The second extra dimension is, therefore, ‘esotericity’. The resulting three-dimensional ‘expertise-space’ can be explored in a number of ways which reveal the narrowness of the analysis and the mistakes that have been made under the one-dimensional model.

Click here for full paper

January 2010

Third Wave criminology: Guns, crime and social order

Adam Edwards and James Sheptycki

Cardiff University, UK, and York University, Canada

Abstract: Evidence-based policy-making implies greater clarity in the relationship between science, politics and crime control. This is especially the case with a highly polarizing topic like gun-crime. Specifically, the enrolment of social science by pressure groups, political parties and other political actors raises questions about the possibility and desirability of a scientifically detached appraisal of the problem. One resolution is to reject the feasibility of objective detachment, treat science and politics as synonymous and locate criminology firmly in the domain of politics and morality—to ‘take sides’ as it were. This renders the purpose of academic criminology problematic, for if its practitioners are to be regarded as inevitably partisan, what do they contribute as social scientists to public issues defined as political and moral in content? Why should criminological knowledge claims be especially valued over that of other political and moral actors? More recently, attempts to define concepts about the formative intentions, intrinsic and extrinsic to the politics of scientists’ work, suggest ways of demarcating science from politics in this and other criminological disputes. They provide a rationale for the distinctive contribution of social science to public controversies over crime and control.

Click here for full paper


November 2008

Counterfeit Scientific Controversies in Science Policy Contexts, SOCSI Working Paper 120

Martin Weinel

Download the paper as a pdf file

Abstract: Experts disagree for many reasons and it is generally accepted that there is no `rational’ way to make them agree. As Michaels (2008) has demonstrated with regard to the activities of the tobacco industry, however, expert disagreement can be ‘manufactured’. This suggests a distinction between ‘genuine’ and ‘counterfeit scientific controversies.’ I argue that it is necessary and possible to distinguish between these two forms of expert disagreement. It is important for policy-making to know which disagreements to take seriously. ‘Counterfeit scientific controversies’ can delay or impede policy-decisions that depend on scientific knowledge. One way for Science & Technology Studies to contribute to science policy-making is to develop a consistent and reliable way to demarcate ‘genuine’ from ‘counterfeit scientific controversies’. This paper proposes four sociologically derived demarcation criteria.




Inna Kotchetkova and Robert Evans (2008) Promoting Deliberation Through Research: Qualitative Methods and Public Engagement with Science and Technology, QUALITI Working Paper 7 (November 2008).

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Abstract: This paper explores the contribution of qualitative research to public engagement with science and technology by critically evaluating a deliberative exercise designed to incorporate several aspects of contemporary science studies. The project used in-depth interviews, reconvened focus groups and a roundtable workshop to simulate ‘upstream’ public engagement by investigating how patients, carers and lay citizens evaluated different treatment options for Type One diabetes. By comparing how these treatments were discussed in focus groups and a roundtable workshop we show how the choice of research setting makes a significant difference to the data collected. In particular, we show that the relatively homogeneous focus groups allowed more perspectives to emerge than the apparently more heterogeneous roundtable, which was ultimately dominated by the patient perspective. In reflecting on these events, we acknowledge both the vulnerability of deliberative methods to factors beyond the researchers’ control but also ask what status the outcome of such deliberations should have if these vulnerabilities could be eliminated.


July 2008

Collins, Harry and Evans, Robert (2008) ‘You cannot be serious! Public understanding of technology with special reference to “Hawk-Eye”‘, Public Understanding of Science, Vol. 17, No. 3 (July), pp. 283-308.

Download the paper from the journal website (requires subscription) or download the paper as an MS Word file

Abstract: Public understanding of science, though it approaches the specialist knowledge of experts only in rare circumstances, can be enhanced more broadly in respect of the processes of science and technology. The public understanding of measurement errors and confidence intervals could be enhanced if “sports decision aids,” such as the Hawk-Eye system, were to present their results in a different way. There is a danger that Hawk-Eye as used could inadvertently cause naïve viewers to overestimate the ability of technological devices to resolve disagreement among humans because measurement errors are not made salient. For example, virtual reconstructions can easily be taken to show “exactly what really happened.” Suggestions are made for how confidence levels might be measured and represented and “health warnings” attached to reconstructions. A general principle for the use of sports decision aids is put forward. A set of open questions about Hawk-Eye is presented which, if answered, could help inform discussions of its use and accuracy.

Key Words: sports decision aids; Hawk-Eye; public understanding of technology; simulations; cricket; tennis.


December 2007

Evans, Robert and Plows, Alexandra (2007) ‘Listening Without Prejudice? Re-discovering the Value of the Disinterested Citizen’, Social Studies of Science, Vol. 37, No. 6, pp. 827-853.
Abstract: Public participation in technological decision-making is increasingly seen as de rigueur, but the limits and purpose of such participation remain open to debate. In this paper we explore the tension between different rationales for widening participation and examine their implications for its practice. Taking debates about medical genomics in the UK as an illustrative example, we argue that more heterogeneous participation and debate have the potential to improve the scrutiny and accountability of science within representative democracies. In doing so we also argue that it is necessary to replace the language of `lay expertise’ with a more systematic and rigorous treatment of the expertise or its absence that characterizes different participants. Drawing on the theoretical work of Collins & Evans (2002), we distinguish between those processes where expert knowledge is required and debate is conducted within the public domain, rather than by the public itself, and those where the views of non-expert lay citizens are needed and valued. The effect of adopting this approach is to permit a more inclusive treatment of the `technical’ while also providing a positive role for non-expert citizens in the democratic control and oversight of science.
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Collins, Harry (ed) Case Studies of Expertise and Experience: Special Issue of Studies in History and Philosophy of Science, Vol. 38, No. 4

Collins, Harry — Introduction: A new programme of research?
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Collins, Harry and Sanders, Gary — They give you the keys and say “drive it”: Managers, referred expertise, and other expertises.
Abstract: On the face of it, the directors of new large scientific projects have an impossible task. They have to make technical decisions about sciences in which they have never made a research contribution — sciences in which they have no contributory expertise. Furthermore, these decisions must be accepted and respected by the scientists who are making research contributions. The problem is discussed in two interviews conducted with two directors of large scientific projects. The paradox is resolved for the managers by their use of interactional and referred expertise. The same analysis might be applicable to management in general. An Appendix, co-authored with Jeff Shrager, compares the notion of referred expertise with contributory expertise.
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Shrager, Jeff — The evolution of BioBike: Community adaptation of a biocomputing platform.
Abstract: Programming languages are, at the same time, instruments and communicative artifacts that evolve rapidly through use. In this paper I describe an online computing platform called BioBike. BioBike is a trading zone where biologists and programmers collaborate in the development of an extended vocabulary and functionality for computational genomics. In the course of this work they develop interactional expertise with one anothers’ domains. The extended BioBike vocabulary operates on two planes: as a working programming language, and as a pidgin in the conversation between the biologists and engineers. The flexibility that permits this community to dynamically extend BioBike’s working vocabulary — to form new pidgins — makes BioBike unique among computational tools, which usually are not themselves adapted through the collaborations that they facilitate. Thus BioBike is itself a crucial feature — which it is tempting to refer to as a participant — in the developing interaction.
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Collins, Harry, Evans, Robert and Gorman, Michael — Trading Zones and Interactional Expertise.
Abstract: The phrase ‘Trading Zone’ is often used to denote any kind of interdisciplinary partnership in which two or more perspectives are combined and a new, shared language develops. In this paper we distinguish between different types of trading zone by asking whether the collaboration is co-operative or coerced and whether the end-state is a heterogeneous or homogeneous culture. In so doing, we find that the voluntary development of a new language community — what we call an inter-language trading zone — represents only one of four possible configurations. In developing this argument we show how different modes of collaboration result in different kinds of trading zone, how different kinds of trading zone may be ‘nested’ inside each other and discuss how a single collaboration might move between different kinds of trading zone over time. One implication of our analysis is that interactional expertise is a central component of at least one class of trading zone.

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Collins, Harry — Mathematical Understanding and the Physical Sciences.
Abstract: The author claims to have developed interactional expertise in gravitational wave physics without engaging with the mathematical or quantitative aspects of the subject. Is this possible? In other words, is it possible to understand the physical world at a high enough level to argue and make judgments about it without the corresponding mathematics? This question is empirically approached in three ways: (i) anecdotes about non-mathematical physicists are presented; (ii) the author undertakes a reflective reading of a passage of physics, first without going through the maths and then after engaging with it and discusses the difference between the experiences; (iii) the aforementioned exercise gives rise to a table of levels of understanding of mathematics, and physicists are asked about the level mathematical understanding they applied when they last read a paper. Each phase of empirical research suggests that mathematics is not as central to gaining an understanding of physics as it is often said to be. This does not mean that mathematics is not central to physics, merely that it is not essential for every physicist to be an accomplished mathematician, and that a division of labour model is adequate. This, in turn, suggests that a stream of undergraduate physics education with fewer mathematical hurdles should be developed, making it easier to train wider groups of people in physical science comprehension.
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Evans, Robert — Social Networks and Private Spaces in Economic Forecasting.
Abstract: The outputs of economic forecasting — predictions for national economic indicators such as GDP, unemployment rates and inflation — are all highly visible. The production of these forecasts is a much more private affair, however, typically being thought of as the work of individual forecasters or forecast teams using their economic model to produce a forecast that is then made public. This conception over-emphasises the individual and the technical whilst silencing the broader social context through which economic forecasters develop the expertise that is essential for the credibility of their predictions. In particular, economic forecasts are given meaning and fine-tuned through the social and institutional networks that give forecasters access to the expertise of a heterogeneous mix of academics, policy-makers and business people. Within these broader groups, individual forecasters often create private forecast ‘clubs’, where subscribers have privileged access to the expertise of the economist, but where the forecasters also have privileged access to their clients’ own expert knowledge. In examining these aspects of the forecasters’ work I show that the visible and audible activities of modelling and forecasting are made possible and plausible by virtue of the modeller’s invisible interaction with a wider network.
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Jenkins, Lekelia — Bycatch: Interactional Expertise, Dolphins and the U.S. Tuna Fishery.
Abstract: The burgeoning field of studies in expertise and experience (SEE) is a useful theoretical approach to complex problems. In light of SEE, examination of the controversial and well-known case study of dolphin bycatch in the U.S. tuna fishery, reveals that effective problem-solving was hindered by institutional tensions in respect of decision-making authority and difficulties with the integration of different expertises. Comparing the profiles of four individuals, who played distinct roles in the problem-solving process, I show that (1) to address a complex problem, a suite of contributory expertises—rarely found in one individual—may be required; (2) formal credentials are not a reliable indicator of who possesses these necessary expertises; (3) interactional expertise and interactive ability are useful tools in combining the contributory expertises of others to yield a desirable collective outcome; and (4) the concepts of contributory expertise and no expertise are useful tools for understanding the actual contribution of various parties to the problem-solving process.
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Ribeiro, Rodrigo — The Role of Interactional Expertise in Interpreting: The Case of Technology Transfer in the Steel Industry.
Abstract: I analyse the case of three Japanese-Portuguese interpreters who have given support to technology transfer from a steel company in Japan to one in Brazil for more than 30 years. Their job requires them to be ‘interactional experts’ in steel-making. The Japanese-Portuguese interpreters are immersed in more than the language of steel-making as their job involves a great deal of ‘physical contiguity’ with steel-making practice. Physical contiguity undoubtedly makes the acquisition of interactional expertise easier. This draws attention to the lack of empirical work on the exact way that the physical and the linguistic interact in the acquisition of interactional expertise, or any other kind of expertise.
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Selinger, Evan, Dreyfus, Hubert and Collins, Harry — Interactional Expertise and Embodiment.
Abstract: In this four part exchange, Evan Selinger starts by saying that Collins’s empirical evidence in respect of linguistic socialization and its bearing on artificial intelligence and expertise is valuable; it advances philosophical and sociological understanding of the relationship between knowledge and language. Nevertheless, he argues that Collins mischaracterizes the data under review and thereby misrepresents how knowledge is acquired and understates the extent to which expert knowers are embodied. Selinger reconstructs the case for the importance of the body in the initial acquisition of language and challenges Collins to show how a disembodied entity could become fluent in any language at all.
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Schilhab, Theresa — Interactional expertise through the looking glass: A peek at mirror neurons.
Abstract: Interactional expertise is here to stay. Undoubtedly, in some sense of the word, one can attain a linguistic expert level within a field without full scale practical immersion. In the context of the idea of embodied cognition, the claim is provocative. How can an interactional expert acquire full linguistic competence without the simultaneous bodily engagement and real life interaction needed to get the language right? How can one understand the concept of hammering if one has never seen a hammer or felt the weight of the iron head on a fragile thumb? Here I will explore a strange and second-hand way in which bodily engagement could have an impact on our linguistic abilities; this is via the so called mirror neuron system. Since the mirror neuron system blurs the distinction between first and third person activity it can help us understand some of the enigmatic aspects of interactional expertise and pose further questions for research.
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Weinel, Martin — Primary source knowledge and technical decision-making: Mbeki and the AZT debate.
Abstract: Demands for public participation in technical decision-making are currently high on the agenda of Science & Technology Studies. It is assumed that the democratisation of technical decision-making processes generally leads to more socially desirable and acceptable outcomes. While this may be true in certain cases, this assumption cannot be generalised. I will discuss the case of the so-called ‘South African AZT debate’. The controversy started when President Thabo Mbeki, after reading some scientific papers on the toxicity of AZT, decided to bar the use of the drug in the public health sector as a means to reduce the transmission of HIV from mothers to children. While the scientific mainstream accepts the effectiveness of AZT in reducing the risk of vertical HIV transmission, a few maverick scientists reject the clinical evidence and argue that the risks of using AZT by far outweigh its benefits. Based on various textual sources and using the ‘periodic table of expertise’ developed by Collins and Evans, Mbeki’s expertise at the time of his intervention into the technical question whether AZT is a medicine or a poison can be classified as primary source knowledge. It is shown that this type of expertise is insufficient for technical decision-making. Mbeki’s primary source knowledge legitimated his presentation of the claims of maverick scientists as a serious contribution to the debate — with tragic consequences for tens of thousands babies
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August 2007

Collins Harry and Evans Robert, (2007) Rethinking Expertise, Chicago: The University of Chicago Press

Collins and Evans’s book on the rationale and contents of the new programme including the Periodic Table and new demarcation criteria between the sciences and non-sciences.

Table of Contents
Preface and Acknowledgements
Introduction: The Role of Expertise in Public Life
Chapter 1: The Periodic Table of Expertises: Ubiquitous and Specialist Expertises
Chapter 2: The Periodic Table of Expertises: Meta-expertises
Chapter 3: Investigating Interactional Expertise and Embodiment
Chapter 4: The Colour-Blindness and Perfect Pitch Experiments
Chapter 5: New Demarcation Criteria
Appendix: Waves of Science Studies


Reviews and features:

American Scientist (2008) Interview with Harry Collins

Scientific American (2008) Interview with Harry Collins

Robert P. Crease (2007) ‘Human Distilleries’, Nature 450 (15 November 2007), 350 – 351.

Robert P Crease (2007) ‘Experts‘, Physics World (August), p. 18.

Matthew Reisz (2007) ‘Expert Opinions’, Times Higher Education Supplement, 7 December 2007, pp. 18-10

Blog Posts

Scenarios and Strategies (25 May 2008):

Will Lion (17 March 2008):

Phil’s JISC CETIS blog (24 Jan 2008):


Ribeiro, Rodrigo (2007) ‘The Language Barrier as an Aid to Communication’, Social Studies of Science, Vol. 37, No. 4, pp. 561-584
Abstract: The communication between distinct social worlds or forms of life is a central topic in the sociology of knowledge. How do different communities interact with each other? Based on a sociological analysis of the work of Japanese—Portuguese interpreters in the Brazilian steel industry, I argue that the `language barrier’, which is normally thought as a problem, can aid communication by preventing people who hold potentially clashing concepts, beliefs and customs from directly confronting each other. The importance for such people of not understanding each other is revealed in the work of interpreters, who facilitate the interaction between representatives of different steel companies and support the transfer of technology from Japan to Brazil. They maintain cordial relationships by acting as `buffers’ between the Japanese and Brazilian forms of life. Three `models of mediation’ are discussed in a comparison of the Japanese—Portuguese interpreters with other cases of interaction.
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March 2007

Collins, HM (2007) Are you fit to call yourself an expert? New Scientist,15 March 2007 full text

Collins introduces the notion of technological populism by imagining the political exploitation of the notion of a terrorist gene. The crucial thing is to use our understanding of expertise to distinguish between real live scientific controversies and ephemeral non-controversies.



December 2006

Collins, H. M. and Evans, Robert, with Ribeiro, R. and Hall, M. (2006) `Experiments with Interactional Expertise’ Studies in History and Philosophy of Science, 37 A/4, [December] 656-74. full text

The Cardiff group’s imitation game experiments with colour blindness, perfect pitch and gravitational wave physics. They show that the colour blind are indistinguishable from colour perceivers because they have been immersed in colour language all their lives whereas those without perfect pitch cannot pretend to have it because they have had little social contact with those few who do have perfect pitch. Collins also passes as a gravitational wave physicist.

Abstract: `Interactional expertise’ is developed through linguistic interaction without full scale practical immersion in a culture. Interactional expertise is the medium of communication in peer review in science, in review committees, and in interdisciplinary projects. It is also the medium of specialist journalists and of interpretative methods in the social sciences. We describe imitation game experiments designed to make concrete the idea of interactional expertise. The experiments show that the linguistic performance of those well-socialized in the language of a specialist group is indistinguishable from those with full-blown practical socialization but distinguishable from those who are not well-socialized. The imitation game can also be used to indicate whether an individual can enter an esoteric domain and master the interactional expertise, a skill required by interpretative sociologists of science, anthropologists, ethnographers, and the like.


Boyce, T. (2006) ‘Journalism and expertise’ Journalism Studies, Vol. 7, No. 6(December), pp. 889-906. full text

Tammy Boyce argues for the importance of distinguishing experts from other sources in the media.

Abstract: Many researchers have observed the paradox of the decline in trust of experts alongside the increasing use of expertise in Western society. This research argues for the division of expertise into a defined category, “expert-source”, separating experts from other sources who do not possess expertise. Using a normative concept of expertise to provide categories can offer a more coherent and consistent method of assessing a source’s expertise and how to present their statements. This research presents findings based on a media analysis of television, radio and newspapers, interviews with journalists and sources and the results of national surveys and focus groups with parents and uses a recent medical controversy in the UK as a backdrop to explore expertise. In 1998 a scientist claimed there might be a link between the measles, mumps and rubella vaccine and autism. His claims received significant media attention and vaccination rates fell across the UK. This case study examines how journalists constructed expertise, how key sources presented themselves as expert-sources and the effect of balancing expert-sources with sources. This research encourages journalists and academics to question how expertise affects media coverage.



August 2006

Carolan, Michael S. (2006) ‘Sustainable Agriculture, Science, and the Co-Production of “Expert” Knowledge: The Value of Interactional Expertise,’ Local Environment: The International Journal of Justice and Sustainability, 11, pp. 421-31. full text

Abstract: After the last few decades in which the importance of ‘local’ knowledge has been emphasized, attention must now turn to better understanding how such knowledge is communicated to certified experts (scientists) and vice versa. This paper examines how expert knowledge is co-produced in agriculture by local and non-local experts for the benefit of both. The argument is informed by an empirical case study of sustainable farmers and agriculture professionals in Iowa. While much has been written about how the conventional and sustainable models of agriculture rest upon different epistemological orientations, little has yet been said about how those different experts (local and certified) interact with each other. Building upon the work of H. M. Collins and Robert Evans, and their tripartite model of expertise (of no, contributory, and interactional expertise), I investigate the different forms of expertise that exist within agriculture. In doing so, specific focus is placed upon interactional expertise for creating meaningful exchanges (or interactions) between scientists and non-scientists.


July 2006

Giles, Jim (2006) ‘Sociologist fools physics judges’, Nature, 6 July 2006, 442, p 8. full text or

Nature reports on Collins’s success in imitating gravity wave physicists.




Collins, H. M. (2004) `Interactional Expertise as a Third Kind of Knowledge’ Phenomenology and the Cognitive Sciences, 3 (2) 125-143 full text

Collins explores the idea of interactional expertise and the difference between social and minimal embodiment.

Abstract: Between formal propositional knowledge and embodied skill lies `interactional expertise’ — the ability to converse expertly about a practical skill or expertise, but without being able to practice it, learned through linguistic socialisation among the practitioners. Interactional expertise is exhibited by sociologists of scientific knowledge, by scientists themselves, and by a large range of other actors. Attention is drawn to the distinction between the social and the individual embodiment theses: a language does depend on the form of the bodies of its members but an individual within that community can learn the language without the body. The idea has significance for our understanding of color-blindness, deafness, and other abilities and disabilities.




Collins, H. M. and Evans, Robert, (2002) `The Third Wave of Science Studies: Studies of Expertise and Experience’, Social Studies of Science, 32, 2, 235-296 full text

Collins and Evans argue that the next step in science studies turns on expertise.

Abstract: Science studies has shown us why science and technology cannot always solve technical problems in the public domain. In particular, the speed of political decision-making is faster than the speed of scientific consensus formation. A predominant motif over recent years has been the need to extend the domain of technical decision-making beyond the technically qualified elite, so as to enhance political legitimacy. We argue, however, that the `Problem of Legitimacy’ has been replaced the `Problem of Extension’ – that is, by a tendency to dissolve the boundary between experts and the public so that there are no longer any grounds for limiting the indefinite extension of technical decision-making rights. We argue that a Third Wave of Science Studies – Studies of Expertise and Experience (SEE) – is needed to solve the Problem of Extension. SEE will include a normative theory of expertise, and will disentangle expertise from political rights in technical decision-making. The theory builds categories of expertise, starting with the key distinction between interactive expertise and contributory expertise. A new categorization of types of science is also needed. We illustrate the potential of the approach by re-examining existing case studies, including Brian Wynne’s study of Cumbrian sheep farmers. Sometimes the new theory argues for more public involvement, sometimes for less. An Appendix describes existing contributions to the problem of technical decision-making in the public domain.



Alternative approaches

This above list of publications is SEE-centred. For a collection of alternative philosophical approaches see:

Selinger, Evan, and Robert Crease (Eds.). 2006. The Philosophy of Expertise . New York: Columbia University Press



Publications on Tacit Knowledge (not in date order)

Tacit and Explicit Knowledge cover

Tacit and Explicit Knowledge

Harry Collins
University of Chicago Press (forthcoming Spring 2010)


Introduction: The idea of tacit knowledge depends on explicit knowledge!

Part I: The Explicit
Chapter 1: Strings and Things
Chapter 2: Digital Strings, Analogue Strings, Affordance and Causes
Chapter 3: Explicable Knowledge

Part II: Tacit Knowledge
Chapter 4: Relational Tacit Knowledge
Chapter 5: Somatic Tacit Knowledge
Chapter 6: Collective Tacit Knowledge and Social Cartesianism

Part III: Looking Backward and Looking Forward
Chapter 7: A Brief Look Back
Chapter 8: Mapping the Three Phase Model of Tacit Knowledge

Appendix 1: An `Action Survey’
Appendix 2: What has changed since the 1970s
References Cited



Ribeiro, Rodrigo and Collins, H.M. (2007) ‘The Bread-Making Machine: Tacit Knowledge and Two Types of Action’, Organization Studies, Vol. 28, No. 9, pp. 1417-1433
Abstract: We analyse Nonaka and Takeuchi’s (1995) claim that a master baker’s tacit knowledge was made explicit and incorporated into a home bread-making machine and its manual — the `knowledge capture’ thesis. In order to test the claim, bread was made without and with a breadmaker and we carried out an analysis of the bread-making actions before and after mechanization. Based on the theory of action morphicity (Collins and Kusch 1998) it is shown that the machine only mimics the mechanical counterpart of just a few of certain special kinds of human bread-making actions. The remaining success of the machine and its manual is due to what other human actors bring to the mechanical bread-making scene; this way the breadmaker can be an adequate social prosthesis. Action mimicking, action substitution, and the contributions of these other human actors, who are not needed in the case of the master baker, explain why the machine and its manual do work. It is not a matter of the explication or incorporation of tacit knowledge, but of fitting a social prosthesis into a rearranged world.
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Collins, H. M. (2007) `Bicycling on the Moon: Collective tacit knowledge and somatic-limit tacit knowledge’ Organization Studies, 28, 02, 257-262 full text

Abstract: The idea of tacit knowledge plays an important role in many areas of academic debate, not least automation and its role in management. Here is it shown that tacit knowledge comes in two distinct types with different causes and consequences. The first kind, `somatic-limit tacit knowledge’ has to do with the limitations of the human body and brain and has no consequences for encoding knowledge into machines. The second kind, `collective tacit knowledge’ is more `ontological’ than biological, having to do with its location in the social collectivity. Here the human body and brain’s unique capacity gives it special access to the tacit knowledge; known and foreseeable machines do not have this capacity.



Collins, H. M., & Kusch, M., (1998) The Shape of Actions: What Humans and Machines Can Do , Cambridge, Mass: MIT Press.

This book develops and explores the idea of polimorphic and mimeomorphic actions in great detail following on from the initial distinction which was explored in Artificial Experts and then called regular actions and machine-like actions. Cases dealt with include bicycle riding, love-letter writing, writing in general, MacDonalds and the mechanisation of air-pumps.


Collins, H. M. (1990) Artificial Experts: Social Knowledge and Intelligent Machines , Cambridge, Mass: MIT press.

This is a Dreyfus-like critique of artificial intelligence but working from a social rather than an individual body perspective. Cases dealt with include the pocket calculator, an expert system for advising on how to make semi-conductor crystals, and the Turing Test. Small differences with the Dreyfus approach are encountered. In particular, the success of the pocket calculator cannot be explained under the social nature of knowledge without inventing the notion of machine-like action — later to be called mimeomorphic action. These small differences with the individual body perspective would become wider and wider over the years to the point that exploration of the social nature of tacit knowledge now looks like a completely new programme.


Collins, H. M. (2001) `Tacit Knowledge, Trust, and the Q of Sapphire’ Social Studies of Science, 31, 1, 71-85 full text

The things that can be learned when one scientist visits another’s laboratory are classified as follows:

1. Concealed Knowledge: A does not want to tell `the tricks of the trade’ to others or journals provide insufficient space to include such details. A laboratory visit reveals these things.

Concealed Knowledge is not very interesting as a `philosophical’ category since the limitations have to do with logistics or deliberate concealment. The next four kinds of tacit knowledge apply even when A has no intention to conceal and there is no shortage of space.

2. Mismatched Salience: There is an indefinite number of potentially important variables in a new and difficult experiment and the two parties focus on different ones. Thus, A does not realise that B needs to be told to do things in certain ways and B does not know the right questions to ask. The problem is resolved when A and B watch each other work.

3. Ostensive Knowledge: Words, diagrams, or photographs cannot convey information that can be understood by direct pointing, or demonstrating, or feeling.

4. Unrecognised Knowledge: A performs aspects of an experiment a certain way without realising their importance; B will pick up the same habit during a visit while neither party realises that anything important has been passed on. Much Unrecognised Knowledge becomes recognised and explained as a field of science becomes better understood but this is not necessary.

5. Uncognized/uncognizable Knowledge: Humans do things such as speak acceptably-formed phrases in their native language without knowing how they do it. Such abilities can be passed on only through apprenticeship and unconscious emulation. Aspects of experimental practice are similar. Uncognizable Knowledge is the most philosophically contentious case: `reductionists’ will want to say that all our abilities will one day be understood at the level of the physics and chemistry of the body and brain so that category 5 will collapse into 4; others believe that abilities such as language are irreducably social accomplishments which means they will never be understood at the level of brain functioning. The debate about whether some or all uncognized knowledge is uncognizable need not concern us when we study the way tacit knowledge works in experimentation for two reasons. First, the fact that language and similar human accomplishments are currently not fully understood means that now, and for the foreseeable future, even that which can be articulated in language rests on a foundation of uncognized abilities even if they are not for ever uncognizable. Second, so long as science continues to develop, new experiments will be continually passing through a stage in which they are not fully understood and certain aspects of the skills required to do them will be passed between experimenters only tacitly.

Abstract: Russian measurements of the quality factor (Q) of sapphire, made twenty years ago have only just been repeated in the West. Shortfalls in tacit knowledge have been partly responsible. The idea of tacit knowledge, first put forward by the physical chemist, Michael Polanyi, has been studied and analysed over the last two decades. A new classification of tacit knowledge (broadly construed), is offered here and applied to the case of sapphire. The importance of personal contact between scientists is brought out and the sources of trust described. It is suggested that the reproduction of scientific findings could be aided by a small addition to the information contained in experimental reports. The analysis is done in the context of fieldwork conducted in the USA and observations of experimental work at Glasgow University.



Collins, H. M. (2001) `What is Tacit Knowledge’ in ~Theodore R. Schatzki, Knorr-Cetina, ~Karin, & von-Savigny, Eike, (eds) The Practice Turn in Contemporary Theory , London: Routledge, 107-119.

Three approaches to tacit knowledge are discussed. The first of these is labelled the `motor skills’ approach and might be called the embodiment approach. The second is the `rules regress’ approach and comes from Wittgenstein’s idea that rules do not contain the rules for their own application. The third is the `social embedding’ approach and proves most fruitful.


Collins, H. M. (1997) `The Editing Test for the Deep Problem of AI,’ Psycoloquy, 8, 1 [Turing Test (8) — electronic journal] full text

A case is made that because of the tacit-knowledge laden nature of language a perfectly adequate Turing Test can be carried out just by asking the computer and human to edit damaged examples of printed texts. The same point is made in Collins, H. M., (1996) `Interaction Without Society?: What Avatars Can’t Do’, in Stefik, M. (ed.), Internet Dreams, Cambridge Mass: MIT Press, 317-326 and reproduced in Rethinking Expertise.



Pinch, T., Collins, H. M., & Carbone, L. (1996) `Inside Knowledge: Second Order Measures of Skill’, Sociological Review, 44, 2, 163-86.

Though it is impossible to reduce tacit knowledge to rules it is possible to provide hints and `second order measures of skill’ that can guide others. We look at a veterinary surgeon who is trying to remove the uterus from a ferret and failing because he cannot find it. He iterates his search six times and then decides to close the wound. Why six times rather than once or 100 times? The surgeon can tell a novice `if you don’t find some organ you are looking for repeat your search around half-a-dozen times and then you will have done the job.’ This is a second order measure of skill. We need second order measures — or at least we need to know how difficult a task is, or we will never learn skilful accomplishments. For example, we need to know it takes a whole afternoon to learn to ride a bicycle and several years to learn to play a piano otherwise we might be disillusioned and think the tasks are impossible. On the other hand one also has to know when to give up.



Collins, H. M. (1989) `Computers and the Sociology of Scientific Knowledge’, Social Studies of Science, 19, 613-24.

Artificial intelligence enthusiasts such as Herb Simon argued that their program, BACON, could make scientific discoveries if fed with data. Collins argues that the art of making scientific discoveries consists of, first, working out which is data and which is noise, and, second, deciding whether some hypothesis makes sense. BACON does neither of these and it is really a deduction engine — certain results simply follow logically from the content of well-defined data. True science is inductive with all the risks that this entails.


Collins, H. M. & Harrison, R. (1975) `Building a TEA Laser: The Caprices of Communication’, Social Studies of Science, 5, 441-50.

Bob Harrison finds he had enormous difficult building a second TEA-laser even though he has a working model that he has built himself on the other side of the lab!


Collins, H. M. (1974) `The TEA Set: Tacit Knowledge and Scientific Networks’, Science Studies, 4, 165-186.

Tacit knowledge is shown to be the key to transferring the ability to build a new kind of laser. Only those who had significant social contact with successful laser builders could do the job. In later work, such as Collins, H. M., (1975) `The Seven Sexes: A Study in the Sociology of a Phenomenon, or The Replication of Experiments in Physics’, Sociology, 9, 2, 205-224 and Collins, H. M., (1985) Changing Order: Replication and Induction in Scientific Practice, Beverley Hills & London: Sage. [2nd edition 1992, Chicago: University of Chicago Press], it is shown that there are deep implications for testing scientific results by repeating others’ experiments. The `Experimenter’s Regress’ arises because the tacit component of a `recipe’ for repeating an experiment prevents one knowing whether the second experiment has been done properly. A failure to repeat then might be always be the result of the effect not being there or the second experimenter’s incompetence.

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