"It shows a singular point, the present, with two cones emanating from it: the observable past and future. Replacing the point with an object (say a chair), the cones become echoing contexts: material, experiential, social, biological, and cultural. In one direction, these contexts become increasingly physical and fundamental. Methods of construction lead to material choices and ultimately biology, geology, DNA, and atoms. In the other, our direct experience with a designed object comes out of and swims in the work and decisions of other people, the way we use objects and form memories with them, and how they fit into our culture. Obstacles wedged into one of these points—in the form of suggestions, amplifications, disruptions, challenges, or prompts—draw the design focus to relationships and result in unanticipated variations."