Creations of human artifice In the twenty-first century, the question most of us ask when disaster strikes is not "How could God let that happen?" but "Who screwed up?" This is a salutary development: We take responsibility for the world we live in. Whether or not our world is the best of all possible worlds, it is a world we have made for ourselves. We live in an engineered landscape, on an engineered planet. Our cities and farms, our dwellings and vehicles, our power plans and communication networks—these are all creations of human artifice. If we don't like it here, we have only ourselves to blame. Brian Hayes, Infrastructure: A Guide to the Industrial Landscape humanityinfrastructuretechnologydisaster
When it goes wrong Kris: It's not my fault when it goes wrong. Jeff: Yes it is. Shane Carruth, Upstream Color lovedisaster
Wang tiles Wang tiles (Hao Wang, 1961) are a class of formal systems. They are modelled visually by square tiles with a color on each side. A set of such tiles is selected, and copies of the tiles are arranged side by side with matching colors, without rotating or reflecting them. The basic question about a set of Wang tiles is whether it can tile the plane or not, i.e., whether an entire infinite plane can be filled this way. The next question is whether this can be done in a periodic pattern. In 1966, Wang's student Robert Berger solved the problem in the negative. He proved that no algorithm for the problem can exist, by showing how to translate any Turing machine into a set of Wang tiles that tiles the plane if and only if the Turing machine does not halt. The undecidability of the halting problem then implies the undecidability of Wang's tiling problem. Wikipedia en.wikipedia.org Truchet TilesThe Tiling Patterns of Sebastien Truchet and the Topology of Structural Hierarchy mathalgorithms