Vicious and Virtuous Cycles
Vicious and virtuous cycles are often caused by a chain of events that exhibit reinforcing behaviour. A virtuous cycle is established in a positive frame; for example, as a result of doing something good, you are rewarded, which enables you to do something better. A vicious cycle is the same feedback structure in a negative frame; for example, as a result of doing something bad, you are penalised, which encourages you to do something worse.
Example applications
Feedback structures are most-commonly seen in systems thinking examples, where causal links are made between variables. Commonly, a the two cycles are linked because of a finite resource; for example, the rich get richer and the poor get poorer. At the extreme, the feedback structure can lead to ‘runaway’ behaviour, such as runaway climate change.
Building a feedback cycle
A simple way of building a feedback cycle is using a Causal Loop Diagram. Note, that vicious and virtuous cycles are both ‘reinforcing’ feedback structures. A ‘balancing’ feedback structure is often referred to as ‘goal-seeking’.
Key concepts
- an overview of the behaviour of vicious and virtuous cycles
- an example of the feedback structure using a causal loop diagram
- advice to the student engineer on how to promote and/or escape these cycles.