Recursion occurs when a thing, being, or event is defined in terms of itself. In broader terms, recursivity – discussed at length by Yuk Hui in his 2019 book Contingency and Recursivity – is the organic or inorganic system’s transformational interaction with the environment. Transformational interactions are often, or at least to a degree, incorporated into the system, and become part of the system’s functioning.
Both organic and inorganic systems act recursively on themselves. Recursion cannot be programmed because all organic and inorganic systems are exposed to errors, accidents, and contingencies they cannot mitigate.