The point really is not operating without inputs, but being able to ignore the ones you’re getting. I think what we’re grasping for here is that the inputs to a controller don’t determine the outputs. That’s interesting because it sounds like one version of free will. When I act freely, my actions were not determined by the environmental inputs. But it’s notoriously hard to explain how that could be so in a deterministic world.

Controllers without programs don’t have outputs regardless of whether they have inputs or not. They are just blank circuitry. Once the circuits are loaded with a program they may be able (may be designed) to operate without inputs but they are not operating from free will. Determinism is built into the cause and effect model. Changing the cause, however subtly, may change the effect but not the model.

Of course, brain circuitry is by no means blank at birth. The very architecture is metametaprogramming. While cause and effect are still operative, this argues that at least some very fundamental aspects of personality are undeniably the result of nature rather than nurture. The model, however, draws the line there, and so long as it rules deteriminism is the inevitable conclusion.