What's that thing called embodiment?

Embodiment has become an important concept in many areas of cognitive science. There are, however, very different notions of exactly what embodiment is and what kind of body is required for what type of embodied cognition. Hence, while many nowadays would agree that humans are embodied cognizers, there is much less agreement on what kind of artifact could be considered embodied. This paper identifies and contrasts six different notions of embodiment which can roughly be characterized as (1) structural coupling between agent and environment, (2) historical embodiment as the result of a history of struct ural coupling, (3) physical embodiment, (4) organismoid embodiment, i.e. organism-like bodily form (e.g., humanoid robots), (5) organismic embodiment of autopoietic, living systems, and (6) social embodiment