It's all pretty meaningless semantics and guesswork. Curve fitting means adaptive computation in networks of fairly simple units that allow for fairly general c

It's all pretty meaningless semantics and guesswork. Curve fitting means adaptive computation in networks of fairly simple units that allow for fairly general computation, i.e. traversing program space to find a good solution, or equivalently, intelligence is about evolving/searching a program that solves a wide array of tasks. It is about finding programs that maps from sensory space to the space of action sequences, maximizing reward. But you need the right prior structure such that learning and producing action sequences is efficient or even feasible/reachable. You can see any additional program structure that aids e.g. generation and recall of memories and planning (production of output targeted at solving a goal) as prior structure that limits and defines the searched program space. You can even regard a planning module as part of the curve fitting as it simply concerns the last step of producing the output. Therefore, intelligence is "curve fitting". So the actual question is: How much additional structure over just a large number of simple repeated units is necessary? Nobody knows. Possibly not much. Possibly quite a bit.