Beyond affordance: tangibles' hybrid nature

A prevalent assumption behind interface approaches that employ physical means of interaction is that this leverages users' prior knowledge from the real world. This paper scrutinizes the assumption that this knowledge can be seamlessly transferred to computer-augmented situations. TEI needs design strategies that acknowledge the hybrid nature of our systems. A change of focus is advocated: from support of intuitive use to the design of seamful mappings and the support of reflection and learning to enable appropriation and a better understanding of the systems we use.