## Part One: The Basics ### More Than the Sum of Its Parts - A system is an interconnected set of elements that is coherently organized in a way that achieves something. A system can be nested within another system. All parts of the system are equally important. - A system consists of: - elements - interconnections - functions and/or purposes - A function is *usually* used for a non-human system. - A purpose is *usually* used for a human one. - Many systems will have both human and non-human elements making the terms almost interchangeable. - Examples of systems: - a school - a city - a tree - roots - trunk - branches - leaves: - within the leaf there are: - cells - chloroplast - water - an animal - a forest >[!important]- Important > **A system is more than the sum of its parts. It may exhibit adaptive, dynamic, goal-seeking, self-preserving, and sometimes evolutionary behavior.** - Elements are easier to notice. They can be both tangible or intangible. They impact the system the least. Elements can be replaced and the system will remain. - Something to consider regarding elements: - How to know whether you are looking at a system or just a bunch of stuff: - Can you identify parts? - Do the parts affect each other? - Do the parts together produce an effect that is different from the effect of each part on its own? - Does the effect, the behavior over time, persist in a variety of circumstances? - Interconnections are the relationship that holds the elements together. The system will change greatly if the interconnections change. - Many of the interconnections in systems operate through the flow of information. Information holds systems together and plays a great role in determining how they operate. > [!quote]- Sufi teaching story > *"You think that because you understand 'one' that you must therefore understand 'two' because one and one make two. But you forget that you must also understand 'and'."* - Functions and purposes are hardest to observe. Often it will require observing for a time to determine what they are. Changes to the function or purpose can be equally as profound as the change in interconnections. > [!important]- Important > The least obvious part of the system, its function or purpose, is often the most crucial determinant of the system's behavior.