Meadows Chapter 1: The Basics

What is a system? Its an interconnected set of elements that is coherently organized in a way that achieves something.

The system must include:

• elements
• interconnectedness
• a function or purpose

EVERYTHING HAS A SYSTEM! 

However, without the interconnectedness or function there is no system. Determining the relationships are more important than defining all the elements. Many interconnections are the flow of information. The elements of a system can be easily changed without harm to the system yet when the interconnections are altered, so is the system.

Stocks are the foundations of systems, the elements you can see, feel count or measure at any given time. Stocks change over time due to flows, a stock is a present memory of the history of changing flows within the system. 

The dynamics of stocks and flows is the behavior over. This helps us learn more about the stocks and flow and how they change. When the level of inflow to outflow does not change, it is called dynamic equilibrium. 

"Stocks take time to change because flows take time to flow"

Feedback loop: a feedback loop is formed when changes in stock affect the flows into or out of that same stock. The feedback loop needs to be stabilized. Feedback loops can also often operate in two directions. Feedback loops can be stabilized with a balancing Feedback loop, these are goal-seeking or stability-seeking. The other type of feedback loop is called a reinforcing feedback loop, this is described as an amplifying, reinforcing and self-multiplying force. This generates more input to a stock the more that is already there. 

That's it for today! That chapter really made me understand quickly what a system is and its real purpose, the loops were slightly confusing but hopefully after next class it'll make more sense.