Integrated Presence in Blended Reality Spaces 9 Integrated Presence in Blended Reality Spaces Giventheproblematicnatureofmixedreality,theneed forblendedreality spacesis clear. We address the problem of designing them by suggesting an approach rooted in a return to first principles of how people understand the world, consciously and unconsciously, and how this determines the way they think, act, an communicate. This, combinedwithaconsiderationof factorsaffectingtheexperienceofpresence, is what we call human-experiential design. Our aim is to support efforts to create the ideal HCI, where there is no extra effort of access to information not effort of action in the world, even though we are located in a reality that combines physical anddigital elements. Human-experientialdesign is a response to the problems of existing approaches to design, which are outlined in Chap. 2. It is based in the cognitive princi- ples of human understanding; specifically, metaphorical projection and blending theory. What this approach brings to the design of blended reality spaces is, initially, the insight that successful design – not least human-computer interaction design – depends on the development and cognitive assimilation of appropriate blends. A blend combines at least two existing conceptual spaces to become a new thing in itself, understood and used almost unconsciously in the lives of users. For example, cutting and pasting with a digital tool has become a thing in itself, but was originally designed and understood on the basis of two conceptual spaces: one composed of paper, paste pots and scissors; the other of computers able to take in information from a source, store it, and output it as required. The new blend is no longer thought of, experienced or used as a combination of two domains, but as a single entity – cutting and pasting. This entity is then available as an input space to further blended, in which cutting and pasting can be combined with anotherconceptualspace,suchascomposingmusic.Chapter3describesthisdesign approachindetail,withaparticularfocusontheimportanceofmetaphorandblends in HCI design. Human-experiential design is also a response to the needs of people for a way of balancing their physical and communicational needs in a new, emerging world. Theseproblemsofdesignincludeamismatchbetweentheconcernsoftechnologies versus the concerns of people. Human-experientialdesign provides a way to bridge contextualgapsinunderstanding,forexamplebetweenyoungandold,betweenhere andthere,andbetweenthetechnologicallysavvyandtherelativelynaïve.Itisaway designing blends of the physical and virtual in which contextual gaps are bridged andwecanfeelaunitarysenseofbeingpresent. Chapters 4 and 5 describe how human-experiential design takes the existing blending approach to HCI design a step further by applying it to the design of combinations of physical and digital realities, making it possible to bridge contextualrealitygapsbetweendistantparticipantsinaninteraction.Inthisprocess, what were previously understood and used as mixed realities become transformed into blended reality spaces. For example, sending text messages on a mobile phone