If you want details on variables, “well-buffered systems” and negative and positive feedback

If you want details on variables, including “critical variables” and “indicator variables” and on “well-buffered systems” and feedback (negative and positive) in a system, read this section from Dӧrner:

…the different ways the variables can affect one another and themselves. …

Positive feedback in a system means that an increase in a given variable produces a further increase in that variable; a decline a further decline.… Positive feedback tends to undermine the stability of a system and a system in which many variables are regulated by positive feedback can easily go haywire.

Negative feedback in a system means that an increase in one variable produces a decrease in another and vice versa. This kind of feedback tends to perpetuate the status quo. It maintains equilibrium in a system and should a disturbance occur, works to return the system to equilibrium….

A system incorporating many variables regulated by negative feedback is a well-buffered system. It can absorb a great many disturbances without becoming unstable [bold added]. But in natural systems, the capacities of buffers are usually limited. A feedback system consumes materials or energy, and if either one is exhausted, the system may collapse.… [Gives water wells as an example.]

The critical variables in a system a system are those that interact mutually with a large number of other variables in the system. They are, then, the key variable: if we alter them, we exert a major influence on the status of the entire system.

Indicator variables are those that depend on many other variables in the system but that themselves exert very little influence on the system. They provide very little influence on the system. They provide important clues that help us assess the overall status of a system. (pp. 74-75)

If you want more quotations from The Logic of Failure

For who Dörner is and the basics about systems and systems thinking, click here. For all of the quotations from The Logic of Failure and these topics, click here:

• What is a system?
• Why is systems thinking necessary?
• What conditions exist in the systems in our world that make them hard to understand?
• Can systems be self-correcting?
• Who thinks well? (Who produces the good outcomes they wanted?))
• Who thinks poorly? (Who produces negative outcomes and outcomes that are opposite to what they declared was their intent?)
• What attributes do not guarantee good thinking?
• How does failure in thinking escalate?
• How can failure escalate?
• How do failures in thinking produce cynicism and fundamental disregard for those people and goals that the decision makers claimed they wanted to help?

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WCJC Department:	History – Dr. Bibus
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Last Updated:	2012 06/04
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