Categorization, Fast and Slow

Abstract. The title of this study is inspired by Daniel Kahneman’s best-selling book Thinking, Fast and Slow. In it, the Nobel Prize winner explains in great detail the working of two systems of human reasoning: System 1, which is fast, automatic, associative, subconscious, involuntary and (nearly) effortless, and System 2, which is slow, intentional, logical, conscious, effortful and requires executive control, attention, and concentration. It is our contention that this distinction applies to human categorization as well. We subscribe to the view that each of the two labels refers, in fact, to a set of systems and call them Type 1 and Type 2 processes. Analyzing and re-interpreting well-known examples found in linguistic literature and our own data, we argue that Type 1 categorization relies on the ‘shallow’ linguistic representation of the world, while Type 2 tends to use ‘deep’ extralinguistic knowledge. The differences between Type 1 and Type 2 categorization are also evident in psycholinguistic experiments and evaluations of linguistic data elicited from speakers. A conclusion is drawn about the need to take this distinction into account in psycholinguistic and linguistic research on categorization.