Walk down any street and look around. The buildings you see will vary in their construction: one, two, or many stories; made of wood, brick, concrete, and steel; heated with oil or gas, cooled with fans and air conditioners; with doors, windows, flat, or peaked roofs. You can give a physical description of them— casual for most of us, more detailed if you’re trained as an architect or engineer. If you could disassemble them, you could put numerical values on the buildings’ differences—so many bricks, that much length of wire and pipe, different quantities of tiles and glass. Article continues after advertisement The construction and maintenance of these buildings requires the coordinated activity of an enormous number of people, spread over space and time. Different people dug up the clay, shaped and fired it into bricks, carted them to the site, and mortared them in place.…