Summary
Virtual and physical embodiments of interactive artificial agents utilize similar core technologies for perception, planning, and interaction and engage with people in similar ways. Thus, designers have typically considered these embodiments to be broadly interchangeable, and the choice of embodiment primarily depends on the practical demands of an application. This paper makes the case that virtual and physical embodiments elicit fundamentally different “frames of mind” in the users of the technology and follow different metaphors for interaction, resulting in diverging expectations, forms of engagement, and eventually interaction outcomes. It illustrates these differences through the lens of five key mechanisms: “situativity, interactivity, agency, proxemics, and believability”. It also outlines the design implications of the two frames of mind, arguing for different domains of interaction serving as appropriate context for virtual and physical embodiments.