Streams of Thought
Cognition is a life process, not a mechanism. It is dynamic, not static. It is a suite of functions and processes, not a hierarchical system. Traditionally, cognition has meant knowledge, especially knowledge of the world. From the ecological point of view, in which knowing is not separated from living, cognition might best be defined as an animal's capacity to keep in touch with its surroundings. As we have seen, this capacity is everywhere subject to perceptual learning: as observers' experiences with their surroundings increase, so does their ability to detect available information. In the case of human beings, perceptual learning is often a collective process, not a solitary one. Through the interactive processes of the field of promoted action, and through various forms of selecting information--gesture, pictures, language--it is groups of humans, not individuals, that most typically embody the cognitive processes.
Contemporary cognitive science knows nothing of cognition as so conceived. Resolutely internalist, individualistic, mechanistic, and mentalistic, the cognitive sciences have studied the cognitive processes as internal information-processing states of single individuals. Doubtless something like these internal states exists, but their relationship to how humans and other animals come to know about their environment is tenuous, at best. At the beginning of this century, Edwin B. Holt (one of William James's students and James Gibson's teacher) had already noted that studying cognition in this way was like trying to understand the rainbow by looking carefully at what goes on in a drop of water and ignoring everything around it. It is not that rainbows aren't made up of drops of water, but simply that rainbows don't exist inside drops-- they exist only when one takes into account other aspects of the environment of the drop: the direction of a light source, the position of other drops of water, and the position of observers.
Because the natural history and ecology of cognition have been completely overlooked by modern psychologists, the material in the present chapter is more speculative than in the previous chapters and less tied to experimental results than I would wish. This is simply because there have been few studies undertaken relevant to how cognition works in everyday life. The reader should thus treat everything that follows as a set of tentative suggestions toward a theory of cognition, and certainly not as a theory of cognition as such. I regret that very little is said about many lines of research on cognition that have been considered important by psychologists in recent years--