What is causal loop diagram (CLD)?

A causal loop diagram (CLD) draws the main variables of a system as labels and connects them with arrows marked plus or minus. A plus means the two move in the same direction, and a minus means they move in opposite directions. The diagram is a quick way to agree on how a system works and to spot the feedback loops inside it.

How it works

You trace the arrows around a closed path and count the minus signs. An even number, including zero, makes a reinforcing loop. An odd number makes a balancing loop. Delays are often marked on the arrows where effects take time. The diagram shows direction and sign, not size or timing, so it cannot predict how fast anything changes. Its strength is conversation: a team can argue about each arrow and expose hidden assumptions before building anything numerical.

Keep the variables to things that can rise and fall, and name them neutrally, for example customer satisfaction rather than good service. Sign errors are easier to catch when each variable has a clear direction of change.

Example

Say a team draws three variables for a restaurant: customers, wait time, and staff. More customers raise wait time (plus). Higher wait time lowers customers (minus). Together that is one minus sign, so the loop is balancing. Adding staff lowers wait time (minus), and a manager adds staff when wait time is high (plus), which is a second balancing loop that works through a delay of hiring. This is an illustration.

How to model it in Machinations

A causal loop diagram is the first sketch, and a Machinations diagram is the next step. Turn each variable into a Pool or Register, each plus or minus arrow into a state connection or a resource connection, and give the arrows numbers. Then Play the diagram to see how large and how fast the loops act.