“Informal histories of HCI commonly document two major intellectual waves that have formed the field: the first orienting from engineering/human factors with its focus on optimizing man-machine fit, and the second stemming from cognitive science, with an increased emphasis on theory and on what is happening not only in the computer but, simultaneously, in the human mind. In this paper, we document underlying forces that constitute a third wave in HCI and suggest systemic consequences for the CHI community. We provisionally name this the ‘phenomenological matrix’. In the course of creating technologies such as ubiquitous computing, visualization, affective and educational technology, a variety of approaches are addressing issues that are bad fits to prior paradigms, ranging from embodiment to situated meaning to values and social issues. We demonstrate the underlying unity of these approaches, and document how they suggest the centrality of currently marginal criteria for design, evaluation, appreciation, and developmental methodology in CHI work.” (Steve Harrison et al. 2007)