How Action Shapes Thought

When you ask someone a question they can’t answer, the response is often a shrug of the shoulders, arms outstretched, elbows bent, palms up. Translated into words, that shrug means “dunno” or “who knows?” An expression of uncertainty. It’s instantly understood that way as well. No need for translation to words, the meaning of the gesture is clear. Now consider another gesture, one made by a preschooler known to shrug her shoulders on other occasions, asking about her day. The answer: not a shrug, but a hand outspread horizontally, teeter-tottering between thumb and baby finger. Or, on another occasion, one thumb up, one thumb down. The shrug seems to say, there’s an answer, but I don’t know it. The information is in the air, but I haven’t caught it. The teeter-tottering hand and up and down thumbs seem to express a different kind of uncertainty, I have the information but it’s not decisive, it goes both ways, It goes up and down, back and forth; it’s balanced. Now I step out of my usual role as a cognitive psychologist and adopt the role of a linguist, where anecdotes are the stuff of thought and analysis. This preschooler distinguishes two fundamental kinds of uncertainty, one where the information might (or might not) be out there but I don’t have it and the other where I have the relevant information but I can’t decide one way or another, the information tilts both ways, Not only does this preschooler know the distinction between the two types of uncertainty, she can express them.

To express either kind of uncertainty –and many other thoughts– she doesn’t use words, she uses gestures. Gestures come faster than words, are more direct than words, and more precise than words. Let’s start with the simplest of gestures, pointing. Babies point long, in baby-time, before they speak. Points direct the eyes to pin-point spots in the world; “there” can’t do that unless accompanied by a string of spatial descriptors that are likely to be vague or wrong or both. From where to how, contrast showing how to open a jar or insert a drawer to explaining how to open a jar or insert a drawer. Gestures truncate and abstract actions in the world to convey actions on things. They also use abstractions of actions to convey actions on thought, raising arguments for and against and placing them on sides of the body, an imaginary whiteboard, then pointing to indicate each side in turn. You have undoubtedly seen speakers do this, you have likely done it yourself; those two sides in space, on your right and on your left, help you keep track of the pros and cons whether you are speaker or listener. Gestures help both speakers and listeners to think and to talk. When asked to sit on their hands, speakers flounder finding words. When people are asked to study and remember descriptions of spatial layouts or actions of mechanical systems, most spontaneously gesture. Their gestures make models of the space or of the actions. When asked to sit on their hands while studying, people remember less and realize fewer of the inferences needed for deep understanding. Thus gestures, abstractions of actions on objects used to represent actions on thought, enable thought and embody thought both for thinkers and for their audiences.

Gestures can be regarded, justly, as diagrams in the air. Gestures are fleeting; transforming them to a page keeps them, and allows scrutinizing them, drawing inferences from them, revising them, by individuals or by groups. Like gestures, graphics use marks in space and place in space to convey meanings more directly than words. Points stand for places or ideas; lines connect them, showing relationships; arrows show asymmetric relations; boxes contain a related set of ideas and separate those from others. Ideas that are close in space are close on any dimension; ideas high in space are high on any dimension, ideas that are central are just that, central. Concepts and relations that are created and understood immediately, in contrast to words, whose meanings are mediated.

Our unnamed preschooler spontaneously expressed two basic senses of uncertainty in her gestures, uncertainty due to absence of information and uncertainty due to indecisive information. Conveying these forms of uncertainty, and perhaps others, for different content in diagrams is still finding its way. Error bars and fuzzy lines are some of the ways diagrams express imprecise quantitative information. Expressing absent or imprecise or undecisive information for qualitative information has been challenging,

Language, too, carries these spatial meanings. We’ve grown closer, or farther apart. The central argument is… Someone’s on the top of the heap or fallen into a depression. That space is wide open, To mix spatial metaphors: navigating the crisis will be a delicate balance.

Spatial thinking is the foundation of all thought. Not the entire edifice but the foundation. All creatures must move in space and interact with things in space to survive. Even plants must move in response to wind, rain, and sun. The evidence comes from many places, from gesture, from language, from diagrams and sketches. It also comes from neuroscience: the same places in hippocampus that represent places are used to represent people, events, and ideas. The same places in entorhinal cortex that map spatial relations also map temporal, social, and conceptual relations, In humans, for the most part, in real space, feet do the navigation and hands do the interaction with things. In conceptual spaces, it’s fingers and hands that navigate in the air or on the screen just as it’s fingers and hands that interact with points in conceptual spaces in the air or on the screen.

Thus, actions in real spaceon objects in real space get truncated and abstracted to form gestures that express actions on ideas in spaces in the air. The same truncated abstracted actions create actions on ideas on the space of the page. This cycle of actions in space that are transformed to gestures that create abstractions in the air or to marks that create abstractions on the page can be unified in the concept, spraction, a contraction for the never-ending cycle of space, action, and abstraction.

Barbara Tversky studied cognitive psychology at the University of Michigan. She held positions first at the Hebrew University in Jerusalem and then at Stanford, from 1978-2005 when she took early retirement. She is an active Emerita Professor of Psychology at Stanford and Professor of Psychology at Columbia Teachers College. She is a fellow of the Association for Psychological Science, the Cognitive Science Society, the Society for Experimental Psychology, the Russell Sage Foundation, and the American Academy of Arts and Science. She has been on the Governing Boards of the Psychonomic Society, the Cognitive Science Society and the International Union of Psychological Science. She is Past-President of the Association for Psychological Science. She has served on the editorial boards of many journals and the organizing committees of dozens of international interdisciplinary meetings.

Her research has spanned memory, categorization, language, spatial cogni- tion, event perception and cognition, diagrammatic reasoning, sketching, cre- ativity, design, and gesture. The overall goals have been to uncover how people think about the spaces they inhabit and the actions they perform and see and then how people use the world, including their own actions and creations, to remember, to think, to create, to communicate. A recent book, Mind in Motion: How Action Shapes Thought, Basic Books, overview that work. She has collab- orated widely, with linguists, philosophers, neuroscientists, computer scientists, chemists, biologists, architects, designers, and artists.