I think the distinctiveness of human beings to other animals is to use a tool. You know, in the Kubrick movie, 2001 A Space Odyssey, a monkey suddenly use a bone as a tool of striking others by the effectiveness of the black monolith. It indicates speciality and superiority of using a tool. If using a tool has specific mean, making a tool may have special meanings for us. Considering so, design seems to have a role like the black monolith.