Chapter 8, page 183
Problem 1: Suppose you are a doctor faced with a patient who has a malignant tumor in his stomach. It is
impossible to operate on the patient, but unless the tumor is destroyed the patient will die.
There is a kind of ray that can be used to destroy the tumor. If the rays reach it all at once at a
sufficiently high intensity, the tumor will be destroyed. Unfortunately, at this intensity the
healthy tissue that the rays pass through on the way to the tumor will also be destroyed. At
lower intensities the rays are harmless to healthy tissue, but they will not affect the tumor
either. what type of procedure might be used to destroy the tumor with the rays, and at the
same time avoid destroying the healthy tissue?
If the participants cannot solve the problem, they are told the answer. The answer is that doctors can use
many small rays sent from many different angles. The rays all pass through different parts of the body and
all converge at the tumor. When the rays converge at the tumor, they add up to produce a high intensity,
which kills the tumor. But when each individual ray passes through the tissue on the way to the tumor, that
ray is not intense enough to destroy healthy tissue.
Figure 8.2: Rays converge at the tumor
tumor
After reading problem 1, people are provided with a new problem such as the following:
Problem 2: An oil well in Saudi Arabia exploded and caught fire. The result was a blazing inferno that
consumed an enormous quantity of oil each day. After initial efforts to extinguish it failed,
famed firefighter Red Adair was called in. Red knew that the fire could be put out if a huge
amount of fire retardant foam could be dumped on the base of the well. There was enough
foam available at the site to do the job. However, there was no hose large enough to put all the
foam on the fire fast enough. The small hoses that were available could not shoot the foam
quickly enough to do any good. It looked like there would have to be costly delay before a
serious attempt could be made. However, Red Adair knew what to do. With his method, the
blaze was quickly extinguished, and the Saudis were satisfied that Red had earned his three
million dollar fee. What did Red do?
The test is to try to solve this problem. The solution is identical in principle to the solution in Problem 1.
The solution is to use many small hoses to shoot foam on the fire from all directions. The foam would
converge on the fire at the center and put it out.
Researchers have consistently found that people who first solve Problem 1 do no better at Problem 2 than
students who have never seen Problem 1. Thus, learning about the “converging rays” solution to the tumor
problem does not help people come up with the similar “converging foam” solution to the blazing fire
problem. People do not transfer information learned on one problem to another problem.