What is infrastucture?

Re-posting something I wrote for another forum because I think it’s good.

Infrastructures are technical objects, often human-made artifacts, which enable some behavior that would not be possible without their invocation. They augment the techniques of their user and are often summoned for some determinate purpose; however, they have no determinate function or set of functions in and of themselves. Furthermore, they may exist at a variety of spatial and temporal scales and be nested within one another. 

These factors allow a great many things to be classified as “infrastructure,” including weapons, tools, biological entities, and even whole terrains. What unifies them, in terms of “sustainability,” is that a given infrastructure requires sustained engagement and modification through time for a purpose. Infrastructures are only infrastructures so long as they are useful for some other, primary end. Infrastructures are never ends in and of themselves. So while they require maintenance, that maintenance is just derivative action and attention.

This raises many interesting philosophical questions, foremost of which is: what can be said to have intentionality? Can living, biological entities? If so, are they the only things? What about celestial objects, as some people have held and hold today?