A system is an entity that the existence of which is maintained via the mutual interaction of its parts and which demonstrates characteristics not exhibited by any of its parts.
We begin with A.
Which influences B.
B then influences A, which A considers to be Feedback.
If we had started with B then the response from A would have been considered Feedback. What is considered Feedback depends on where you look at things from.
A System is an entity who's existence if maintained via the mutual interaction of its parts. - Bertalanffy
Seldom does anything actually exist in isolation. As such we create a boundary so we know what's part of the system and what's part of it's environment.
A system exhibits characteristics not produced by any subset of its parts. These are emergent properties.
A system is an entity who's existence is maintained via the mutual interaction of its parts and which exhibits characteristics not found in any of its parts.
Systems don't exist. What exists are descriptions of a set of relations, their interactions, their boundary, their interaction with their environment and emergent characteristics. A System is an individual's abstraction of some set of relations to server a particular intent.
The best advice I can offer is, when one says "the system" you should immediately respond with, "What does that mean."
For you to understand what they mean they have to identify the parts, the interactions, the boundary, interaction with the environment, and emergent characteristics. Would anything less be simply muddled thought?