The richness of human knowledge and understanding is far deeper than the set of knowledge we can produce a symbolic account of. As Polanyi puts it, “we know more than we can tell” [56, p. 4]. To elucidate this assertion, consider riding a bicycle: one is simultaneously navigating, balancing, steering, and pedaling; yet it is not possible for bicyclists to articulate all of the nuances of an activity that they successfully perform. Perhaps the most remarkable aspect of this is that riding a bicycle is just one of thousands of activities that our bodies can do.
Contrast the richness, subtlety, and coordination of tasks at several levels of concern that bicycling offers with the graphical user interface that we use today. One of the most sweeping — and unintended — transformations that the desktop computing paradigm has brought about is the extent to which the physical performance of work has homogenized. For certain activities, such as writing this paper, the keyboard interaction paradigm appropriately leverages our bimanual dexterity. But, with a keyboard and mouse interface, the use of our bodies for writing a paper is the same as for editing photographs. And playing music. And communicating with friends and family. And anything else that one might want computation for.
This paper presents five themes that we believe are particularly salient for designing and evaluating interactive systems. The first, thinking through doing, describes how thought (mind) and action (body) are deeply integrated and how they co-produce learning and reasoning. The second, performance, describes the rich actions our bodies are capable of, and how physical action can be both faster and more nuanced than symbolic cognition. The first two themes primarily address inspanidual corporeality; the next two are primarily concerned with the social affordances. Visibility describes the role of artifacts in collaboration and cooperation. Risk explores how the uncertainty and risk of physical co-presence shapes interpersonal and human-computer interactions. The final theme, thickness of practice, suggests that because the pursuit of digital verisimilitude is more difficult than it might seem, embodied interaction is a more prudent path.
To be sure, this paper is not the first to posit that richer interaction paradigms are possible. What we hope to contribute to this discussion is a synthesis of theoretical and empirical work— drawn from psychology, sociology, and philosophy — that provides insight for both ideation and evaluation of interaction design that integrates the physical and computational worlds.