In a previous post, I set out five different understandings of knowledge. One of them was practical knowledge – knowledge of how to do a particular skill. Practical knowledge is a name applied to the knowledge required to do a particular kind of skill, but it can be reduced to other forms of knowledge.
In order to understand practical knowledge, let’s begin with an example. Suppose that we start with someone who is learning to play the piano. This certainly counts as an example of practical knowledge. At the beginning, the piano player begins by knowing nothing about how to play. At the very beginning, the piano player is given an amount of theoretical knowledge about pianos. This includes such things as where the notes are and how musical notation is properly understood. Now the player knows in one sense and is ignorant in another. Next, the piano player is told how to play the piano. They may observe the teacher playing and listen to the teacher give them advice on how to properly play the piano. This will include such things as how to properly place one’s hands on the keyboard, how hard to hit the keys and which fingers to use when playing. This is factual knowledge. Finally, the piano player is told to practice and improve. By gaining experience playing, one learns. This is experiential knowledge. By the time the piano player has mastered the ability to play particular songs, they have gained some theoretical knowledge, some factual knowledge and some experiential knowledge. There is no need to suppose a further category of practical knowledge to explain the piano player’s knowledge.
There is one further aspect to consider. Suppose we consider the skill of playing a piano to be more than simply playing songs correctly. Those who have achieved a complete mastery of piano playing also display an aspect of creativity. Songs are not intended to be played the exact same way every time. They are intended to played as best fits the situation. There is also an element of originality in playing. So there are two sides to complete mastery an instrument. One side is doing things at the right time, in the right way and in the right circumstances. This is just another name for the virtue of wisdom. It is not an aspect of knowledge, but a perfection of action. The other side is simply creativity itself. Creativity is simply an indirect expression of truth as that truth best fits the circumstances. It is not a special kind of knowledge either.
None of this description requires a distinct kind of knowledge called practical knowledge. So it seems best to understand practical knowledge as that kind of knowledge that is is required in order to do a particular kind of activity well. It is composed of theoretical, factual and experiential knowledge. This knowledge is always aimed at a particular activity. But activity does not make the knowledge one kind of thing. We only know what the knowledge is because we consider what knowledge is required to do the activity. The point of doing the activity is the activity, not the knowledge gained from it. So there is no special reason to suppose that practical knowledge is something different from the other kinds of knowledge. So considered as a kind of thing, there is no such thing as practical knowledge.