Michael Polanyi’s ‘Tacit Knowledge’
What is ‘tacit knowledge’? In his seminal volume, Michael Polanyi (1962) writes that:
[t]he act of knowing includes an appraisal; and this personal coefficient, which shapes all factual knowledge, bridges in doing so the disjunction between subjectivity and objectivity.
(Polanyi 1962: 17)
One of the strengths of Polanyi’s thought is its strong rejection of dualistic tendencies; such as between theoretical and practical knowledge. For him, ‘[a]ll knowing is personal knowing – participation through indwelling’ (Polanyi and Prosch 1975: 44). Therefore, the idea that there could be such a thing as objective knowledge is mistaken and destructive; rather, all knowledge involves the active participation of the knower. The act of knowing is skilful action.
For example, imagine that I wish to construct a model airplane. In order to achieve this from a boxful of plastic pieces of different shapes and sizes I might make use of a set of diagrams and instructions. Each diagram is an explicit representation of something other than itself, a model airplane. It is, in this way, similar to a system of rules, aimed at bringing about purposeful action. But in order to utilise the potential of those diagrams I will first need to be able to relate them to the physical world outside them: I must read the diagrams. In fact, I must do three things: identify the pieces that I have, choose what I want to make, and decide how to put them together. According to Polanyi, all such acts are acts of skilful judgement and they are both cognitive and sensual (Polanyi 1962: 10–20). The diagrams assist me in constructing the model, matching individual pieces to their diagrammatic representations, but this still requires some personal judgement on my part to match the two, a mental and physical effort, in short, a skilful action. Personal judgements such as this are involved whenever we try to bring together our experience of the world and our abstract representations of it. We often say that certain laws can predict certain outcomes, but what we really mean is that we can predict certain outcomes by using these laws as tools. The outcomes are not given; rather, they need to be calculated, checked and authenticated, comparing expectations with results, calculating margins for error and assessing and reassessing the reliability of our rules (Polanyi 1962: 19).
In arguing that our tools of perception, intuition and reasoning are not self-applying but require an action on our part in order to apply them, Polanyi, like Whitehead, emphasises the importance of the physical body in the act of knowing:
the way the body participates in the act of perception can be generalized further to include the bodily roots of all knowledge and thought … Parts of our body serve as tools for observing objects outside and for manipulating them.
(Polanyi 1969: 147)
In this sense, Polanyi argues that all acts of knowing are skilful presentations by the human agent which involve a ‘personal coefficient’ (Polanyi 1962: 17). Moreover, each skilful performance ‘is achieved by the observance of a set of rules which are not known as such to the person following them’ (Polanyi 1962: 49). Consider the driver of a motor vehicle. Although not well acquainted with the scientific principles of internal combustion such a driver may nonetheless be quite capable of driving proficiently. She will move off, effortlessly, from a stationary position and continue driving along a busy road, maintaining the car in a forward direction with good speed and with minimum discomfort to her passengers, accelerating and decelerating, changing gears up and down as necessary. Of course, if she were able, she might formulate rules based on scientific principles to explain why it is that the car responds in particular ways to the different actions she performs but it is not at all obvious that knowing any of these scientific rules would necessarily make her a better driver; much less, that she would require to know anything about these rules simply to drive. As she learns to drive and becomes more proficient at driving, any such knowledge will usually be held ‘at the back of her mind’, not focused on but taken for granted, accepted and held unconsciously. Just so, we might say that skills such as driving are not normally held to be accountable fully in terms of their particulars; indeed, these are often unknown to the person exercizing the skill. Knowing how a car works will not of itself make someone a good driver (Polanyi 1962: 88–90).
According to Polanyi, every ‘mental effort … tends to incorporate any available elements of the situation which are helpful for its purpose’, even without the actor knowing them in and of themselves. Thus, it has a heuristic effect:
we feel our way to success and may continue to improve on our success without specifiably knowing how we do it – for we never meet the causes of our success as identifiable things which can be described in terms of classes of which such things are members.
(Polanyi 1962: 62)
Here, two types of awareness are involved. Polanyi uses another example to explain. Suppose that I am engaged in hammering a nail into a piece of wood. While I am aware both of the hammer and the nail, my awareness of the hammer is different to my awareness of the nail. Driving the nail into the wood is the main object of my concentration and I watch and correct my action as the effects of my hitting the nail drive it further into the wood: I am focally aware of the nail. I am also aware of the hammer: I feel it clenched tightly in my hand. However, feeling the hammer in my hand is not the main focus of my concentration:
I know the feelings in the palm of my hand by relying on them for attending to the hammer hitting the nail. I may say that I have a subsidiary awareness of the feelings in my hand which is merged into my focal awareness of my driving the nail.
(Polanyi and Prosch 1975: 33)
In other words, in performing an action, I am aware of some things that are not the main focus of my attention. More precisely, ‘in an act of tacit knowing we attend from something for attending to something else’ (Polanyi 1966: 10), which is why we always ‘know more than we can tell’ (Polanyi 1966: 4).
We can compare this understanding of skilful engagement with the legal method of deductive syllogism. On the one hand, we should note that on this understanding tacit integration cannot be undone: it is certainly possible to shift one’s attention away from the object of one’s concentration while driving a motor car or hammering a nail, often with significant results, but this will not take one back to the point of not knowing how to drive a car or hammer a nail. On the other hand, in the deductive syllogism we find that we can proceed step by step in a logical way from premises to conclusions and back again always without loss. In other words, because all the logical connections hold then the direction is reversible. Now, if we think of a particular instance of judicial decision-making, it should be clear that the moment of the decision in which the judicial decision is made is essentially one of tacit integration, while the subsequent act of providing justifying reasons for that legal decision is essentially, as MacCormick argues, of the nature of explicit or deductive inference. Clearly, the two are not the same. While the latter may build upon the former and may even explain it for legal purposes, this, as Christodoulidis observes, comes too late to justify it, for there is no going back. What is purportedly a justifying reason may indeed provide a reason to explain why the decision, already made, may now be used as a relevant datum for new decisions, but that is a quite different thing to saying that it provides the justifying reason in and through which that decision was made.
Clearly, much of this also taps into the familiar realist debate concerning the ‘judicial hunch’ and, in that respect, precisely what part is being played here by ‘discovery’ and what by ‘justification’. This distinction was first made by Hans Reichenbach (1955) in order to differentiate between the description of the origin of a proposition (the ‘context of discovery’) and the demonstration of it (the ‘context of justification’); indeed, Reichenbach argued that:
[t]he act of discovery escapes logical analysis; there are no logical rules that could be applied to the construction of a ‘discovery machine’ that would assume the creative function of genius. But it is not the logician’s task to explain scientific discoveries; all the logician can do is analyse the relation between the facts as given and a theory that is presented to her or him that claims to explain this relation. In other words, logic is not concerned with the context of discovery.
(Reichenbach 1955: 199)
All of which brings us back once again to the central problem highlighted by Christodoulidis.