The Logic of Failure Quotes

“If we want to solve problems effectively...we must keep in mind not only many features but also the influences among them. Complexity is the label we will give to the existence of many interdependent variables in a given system. The more variables and the greater their interdependence, the greater the system's complexity. Great complexity places high demands on a planner's capacity to gather information, integrate findings, and design effective actions. The links between the variables oblige us to attend to a great many features simultaneously, and that, concomitantly, makes it impossible for us to undertake only one action in a complex system.


A system of variables is "interrelated" if an action that affects or meant to affect one part of the system will also affect other parts of it. Interrelatedness guarantees that an action aimed at one variable will have side effects and long-term repercussions. A large number of variables will make it easy to overlook them.

We might think of complexity could be regarded as an objective attribute of systems. We might even think we could assign a numerical value to it, making it, for instance, the product of the number of features times the number of interrelationships. If a system had ten variables and five links between them, then its "complexity quotient", measured in this way would be fifty. If there are no links, its complexity quotient would be zero. Such attempts to measure the complexity of a system have in fact been made.

Complexity is not an objective factor but a subjective one. Supersignals reduce complexity, collapsing a number of features into one. Consequently, complexity must be understood in terms of a specific individual and his or her supply of supersignals. We learn supersignals from experience, and our supply can differ greatly from another individual's. Therefore there can be no objective measure of complexity.”
― Dietrich Dorner, The Logic of Failure: Recognizing and Avoiding Error in Complex Situations

“When we set out to change things, we don't pay enough attention to what we want to leave unchanged.”
― Dietrich Dörner, The Logic of Failure: Recognizing and Avoiding Error in Complex Situations

“We have a tendency, under time pressure, to apply overdoses of established measures.”
― Dietrich Dörner, The Logic of Failure: Recognizing and Avoiding Error in Complex Situations

“When we are asked to act, we do so only if we feel at least minimally competent to do what is asked of us. We need to feel that our actions will ultimately be successful. Without some expectation of success, we are unlikely to act at all and will rather resign ourselves to letting fate take its course. We often redirect our thinking from our actual goals to the goal of preserving a sense of our competence. This act of self-protection is essential to maintaining a minimum capacity to act.”
― Dietrich Dörner, The Logic of Failure: Recognizing and Avoiding Error in Complex Situations

“New information muddies the picture. Once we finally reach a decision, we are relieved to have the uncertainty of decision making behind us. And now somebody turns up and tells us things that call the wisdom of that decision into question again. So we prefer not to listen.”
― Dietrich Dörner, The Logic of Failure: Recognizing and Avoiding Error in Complex Situations