Theory of Constraints Handbook - James Cox Iii [523]
FIGURE 25-B2 Entity Existence Reservation
FIGURE 25-B3 Causality Existence Reservation
FIGURE 25-B4 Additional Cause Reservation
By using the cause insufficiency reservation, the listener is indicating that he or she believes that the current cause entity is insufficient by itself to cause the effect entity. It is begging the question that something else must also exist in addition to the current cause to create the effect. A “conceptual and” connector is usually required to satisfy this reservation. If cause entity and entity (or core driver) then effect entity. The connector is diagrammed as an ellipsis (sometimes called a banana) or line across the arrows. In Fig. 25-B5, the reviewer is challenging that entity 10 “We have not settled on a new union contract” could cause 25 “Our employee morale is low.” She suggests that a more accurate explanation is: If 15 “The current contract expires at the end of the month” and 10 “We have not settled on a new union contract” then 25 “Our employee morale is low.”
The house on fire reservation (sometimes called the cause-effect reversal) is used to challenge the thought pattern where the cause and effect seem reversed. This usually occurs where the presenter confuses why the effect entity exists with how we know that the effect entity exists. For example (see Fig, 25-B6), if (cause) smoke is billowing from a house then (effect) the house is on fire is not valid logic. An electrical short circuit may cause the house being on fire. If (cause) the house wiring had an electrical short circuit then (effect) the house is on fire. The cause of the fire is a short circuit in the electrical wiring. The original statement is how we know the house is on fire, not the cause of the fire. The smoke billowing from the house is the result of the house being on fire. We have confused the cause with the effect. Ask “why” to determine the cause.
The predicted effect existence reservation is used to explain why you disagree with the presenter’s previous explanation and generally is the last reservation used. In this challenge, you are prepared to show the presenter that his or her logic is flawed. There are two types of challenges—one questioning the existence of the cause entity and the other questioning the existence of the causality between the two entities. This challenge is presented by providing a counter example that if the predicted effect is present, then the cause cannot be present or if the effect is absent, then the cause cannot be present. In Fig. 25-B7, If 10 “Our quality has deteriorated significantly” then 25 “Our profits have decreased significantly” would be validated by the existence of 35 “Our returns and field service expenses have increased significantly.” However, in examining our expenses this effect does not exist. The reviewer then challenges the existence of entity 10. Suppose the cause entity exists—what other predicted effect must be present? If that predicted effect is not present, then the cause is not present. Likewise, if the predicted effect exists it adds validity to entity 10 being the true cause of 25.
FIGURE 25-B5 Cause Insufficiency Reservation
FIGURE 25-B6 House on Fire Reservation
The challenge can be based on the existence of the causality—predicted effect reservation for 10 to 20. In the example in Figure 25-B7, If 10 The packaging line broke down then 20 The AJAX shipment is late is challenged for causality—while the reviewer believes that both 10 and 20 exist, she does not believe that 10 caused 20. She offers as proof that the packaging line broke down after the AJAX order was completed; therefore, the line breaking down did not cause the order to be late.
FIGURE 25-B7