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Three dimensions of expertise


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 programme 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.

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  1. References to work pertaining to SEE will be found throughout this text.

  2. This workshop was held on the Berkeley campus on 8–9 August 2010, overlapping with the annual meeting of the International Society for Psychology of Science and Technology (which ran over the previous 2 days). This paper is a version of my presentation to that meeting, though it has been much amended in the light of what transpired over the next 2 or 3 days. I am indebted to the lively critical discussions which, by the end of the meeting, had taken on a constructive and genuinely interdisciplinary flavour. I am especially grateful to Greg Feist for critical comments and Rob Evans for positive input, especially to the Expertise-space diagrams which contain a number of his ideas.

  3. Thanks to Greg Feist for the reference to Chi.

  4. For the latest and most radical version of this position, see Collins (2011b).

  5. Grene 1969, p 144

  6. I originally called it the ‘Expertise Phase Diagram’ as it was inspired by chemical phase diagrams that I remember from (high) school. The idea of phases suggests sudden transitions. The existing analysis of expertise is, of course, filled with such discontinuities. There are the stage theories that have already been mentioned. There are the discontinuities in child development discussed by Shrager. There is a lingering notion that, stages aside, something special happens as you move up the vertical axis. There is the discontinuity between mimeomorphic and polimorphic actions (Collins and Kusch 1998) and the difference between Relational, Somatic and Collective tacit knowledge (Collins 2010). The difference between interactional and contributory expertise is central (with what Ribeiro calls, ‘physical contiguity’ located in-between) and the entire Periodic Table of Expertises is full of classes and therefore discontinuities. Also, the Imitation Game idea (Collins and Evans 2007) has some sense of discontinuity about it when we speak, in certain special circumstances, of people ‘passing’ or ‘failing’. There is, therefore, too much to represent on the diagram and it seems better to think of all three axes as continuous. It may be that the table is seriously flawed in not recognising some important discontinuities at the outset. But, to move from this default position and establish that some unrepresented boundary has vital analytical significance and/or renders the table incoherent requires argument and justification.

  7. Gravitational wave physics is regularly used as an example since the author of this paper has spent nearly 40 years immersed in the field on and off. See for example, Collins 2004a, 2011a.

  8. Theresa Schilhab continues to press upon me that the acquisition of ‘Somatic Tacit Knowledge’, which, to simplify, is sets of physical procedures embedded in body and nerve pathways such as that required to balance on a bicycle (Collins 2010), is less dependent on immersion in a culture. You can, as it were, learn to balance on a bike all by yourself. There may be some truth in this, but I prefer to concentrate on the fact that you would be unlikely to know what a bike was for if you were truly isolated. Schilhab’s point should not be forgotten nevertheless.

  9. For those who might like to work with these surfaces but don’t know how draw them, go to ‘autoshapes’, ‘lines’, and then choose the closed irregular loop. Click on a point in the original figure and then go the next point and click again. Go from point to point until the loop is closed and then double-click. This creates a straight-edged figure that can be coloured, shaded, etc. Right-click within this figure (usually once, but sometimes one seems to need to do it twice), and choose ‘edit points’. The corners of the figure can then be dragged into the exactly right places so as to fine-tune the shape. Clicking anywhere on a straight edge generates a new ‘point’ which can be dragged to create a more complicated shape. The same method is used to create areas of shading (choose ‘no lines’) that are used to fill existing features such as the domain ‘floors’.

  10. Rob Evans worked out the meaning of the two voids.

  11. It is surely worth recounting that, at the Berkeley meeting, one delegate insisted that only esoteric expertises counted as expertises and that car-driving was not one of them. He insisted that the Dreyfuses’ analysis (Dreyfus and Dreyfus 1986) showed this clearly. Bert Dreyfus, however, attended the workshop on the crucial morning and, as when Woody Allen brought Marshall McLuhan to the cinema queue, Dreyfus was able to deny in person that he thought it might be better to think of ubiquitous expertises as expertises proper and that car-driving was certainly a case in point and had been treated as such in his own works.

  12. The language point is also made in Collins and Evans 2007, p3.

  13. See Collins and Kusch 1998 and Collins 2010 for more extended discussions of why this is so.

  14. If I was forced to choose between the two, I would say that driving a Formula 1 car is a completely different activity to street driving.

  15. For an explanation of these kinds of tacit knowledge see Collins 2010.

  16. For the argument see Collins and Kusch 1998 and Collins 2010.

  17. Tom Seager, Dave Stone and Evan Selinger are all involved in thinking along these lines.

  18. Anything that involves ‘loyalty’ to a philosophical cannon belongs, at best, in the lobes. Loyalty is best treated with suspicion. Misplaced loyalty to methods and perspectives has damaged sociology and, I suspect, it has damaged psychology. What matters is what works.

  19. This relates to the earlier question raised by Schilhab (note 8)

  20. In Collins (2010) it is argued that animals should not be said to have tacit knowledge because they do not have explicit knowledge and the idea of the former makes sense only when it is in tension with the later; were this not so then a sieve would have to be said to have the tacit knowledge of how to sort stones and a tree of how to grow leaves.


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Correspondence to Harry Collins.

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Collins, H. Three dimensions of expertise. Phenom Cogn Sci 12, 253–273 (2013).

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  • Expertise
  • Studies of expertise and experience
  • Tacit knowledge
  • Ubiquitous expertise
  • Stage theories