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TOC Thinking Processes

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Simply stated, the Thinking Processes (TP) involve the rigorous application of cause-effect logic to solve a problem. There are 6 basic tools that make up the thinking processes. Each can be used independently or they can be used in various combinations depending on the need at the time. The TP are listed below, followed by a primary independent use.

  • Current Reality Tree (root cause analysis)
  • Evaporating Cloud (conflict resolution)
  • Future Reality Tree (solution testing)
  • Negative Branch ( negative side-effect abatement)
  • Prerequisite Tree (reaching an ambitious target)
  • Transition Tree (fail-safe action planning)

 The TP can be used together when an organization is underperforming. This is done by using the TP to answer, in sequence, the following three questions:

  1. What to Change?
  2. To What to Change?
  3. How to Cause the Change?

The first question is the most important and often the most difficult question to answer. There is usually no physical evidence to point you to the core problem in a complex environment. Instead you have to "map out" what is currently going on in your system. The logical mapping structure that is used at this point, is the "Current Reality Tree." This is not a simple task, but when it is completed successfully, you will know what to change.

That will bring you to the question, "To what to change?" There are two distinct steps to answering this question.

  1. Identify a breakthrough idea, or "injection", that will overcome the problem(s) identified in the current reality tree.
  2. Ensure that the "cure" that is derived will not be worse than the "disease."

The "Evaporating Cloud" is used to break through the core conflict that is currently blocking the organization from fully exploiting or subordinating to their constraint. Applying the breakthrough idea to the organization is analogous to a doctor revitalizing a patient by giving him/her an injection, and so the breakthrough idea is referred to in TOC terminology as an injection.

The "Future Reality Tree" is developed next to ensure that the undesirable effects you now are experiencing will, indeed, be changed to desirable effects by the injection. The unintended negative consequences of the proposed solution are usually identified at this point using what are called Negative Branches. If these bad things that result from a good action can be prevented, then you can be sure the "cure" (the injection) will not be worse than the "disease". Now you know what to change to.

That brings you to question 3, "How to cause the change?" The simple answer is: get the people who are going to have to live with the change to create the action plan that is needed for implementation. The Thinking Processes pro-actively involve those who are most effected by the change. These people are solicited for their vision of what obstacles might prevent the organization from moving forward on this breakthrough solution. The workers are used to generate all the additional ideas that are necessary to implement the original injection. Once these are known, a plan is mapped out. The tools used when answering question 3: the "Prerequisite Tree," and the "Transition Tree."

"Even if a company has good leadership and dedicated and enthusiastic workers, weak tools will produce only confusion, frustration, and disenchantment."


- Keki R. Ghote, World Class Quality, (AMACOM, 2000)