In The Logic of Failure, German psychologist Dietrich Dörner summarized experiments on how people deal with complex systems. Dörner created a computer model of an imaginary country in West Africa that he called Tanaland. The people of this imaginary land depend on growing crops, gathering fruit, and herding sheep and cattle. Participants in Dörner’s experiment were given the opportunity to control certain variables of the Tanaland computer model, such as whether to use irrigation and fertilizer. Most participants quickly wiped out Tanaland’s population, but a few were able to preserve a healthy rate of growth. The differences between the experiment’s two groups, Dörner wrote, were striking: “The good participants acted more complexly. Their decisions took different aspects of the entire system into account, not just one aspect. This is clearly the more appropriate behavior in dealing with complicated systems,” he added, because complexity means there are “many interdependent variables in a given system,” which makes “it impossible to undertake only one action.”