Our society is divided into castes based upon a supposed division between theoretical knowledge and practical skill. The college professor holds forth on television, as the plumber fumes about detached ivory tower intellectuals. The felt distinction between the college professor and the plumber is reflected in how we think about our own minds. Humans are thinkers, and humans are doers. There is a natural temptation to view these activities as requiring distinct capacities. When we reflect, we are guided by our knowledge of truths about the world. By contrast, when we act, we are guided by our knowledge of how to perform various actions. If these are distinct cognitive capacities, then knowing how to do something is not knowledge of a fact — that is, there is a distinction between practical and theoretical knowledge. The world of the college professor is supposedly so different than the world of the plumber because they are viewed as employing fundamentally different mental capacities in their daily lives. The college professor doesn’t “get it,” because her knowledge is purely theoretical, knowledge of truths. The plumber isn’t qualified to reason about a political system or the economy because skill in complex action is not an exercise of such knowledge.
According to the model suggested by this supposed dichotomy, exercises of theoretical knowledge involve active reflection, engagement with the propositions or rules of the theory in question that guides the subsequent exercise of the knowledge. Think of the chess player following an instruction she has learned for an opening move in chess. In contrast, practical knowledge is exercised automatically and without reflection. The skilled tennis player does not reflect on instructions before returning a volley — she exercises her knowledge of how to return a volley automatically. Additionally, the fact that exercises of theoretical knowledge are guided by propositions or rules seems to entail that they involve instructions that are universally applicable — the person acting on theoretical knowledge has an instruction booklet, which she reflects upon before acting. In contrast, part of the skill that constitutes skill at tennis involves reacting to situations for which no instruction manual can prepare you. The skilled tennis player is skilled in part because she knows how to adjust her game to a novel serve, behavior that does not seem consistent with following a rule book.