Perhaps ironically, the various branches of “systems thinking” do not have a consensus definition of “system” archetypes. In “Ackoff’s Best”, Russell Ackoff lays down his definition as follows:
There are three basic types of systems and models of them, and a meta-system: one that contains all three types as parts of it. 1. Deterministic: Systems and models in which neither the parts nor the whole are purposeful (e.g. a computer) 2. Animated: Systems and models in which the whole is purposeful but the parts are not (e.g. you or me). 3. Social: Systems and models in which both the parts and the whole are purposeful (e.g. an institution). All three types of systems are contained in ecological systems, some of whose parts are purposeful but not the whole. For example, Earth is an ecological system that has no purpose of its own but contains social and animate systems that do, and deterministic systems that don’t.
But wait! Why are there no Ackoffian systems whose parts are purposeful but whose whole is un-purposeful? Russ doesn’t say why, but BD00 (of course) can speculate.
As soon as one inserts a purposeful part into a deterministic system, the system auto-becomes purposeful?
