Modern Research on Problem Solving • 331only 23 percent in the mental set group used this solution
for these problems. Clearly, participants in the mental set
group learned the procedure described by the formula B − A
− 2C as they solved problems 1 to 6 and simply continued to
apply that procedure to solve problems 7 and 8. The mental
set created by solving problems 1 to 6 inhibited them from
using the simpler solution for 7 and 8.
The Gestalt psychologists were the pioneers of problem-
solving research. Between about 1920 and 1950, they
described problems and solutions illustrating how mental set
can infl uence problem solving and how solving a problem
often involves creating a new representation. This idea that
problem solving depends on how the problem is represented
in the mind is one of the enduring contributions of Gestalt
psychology. Modern research has taken this idea as a starting point for the information-
processing approach to the study of problem solving.Modern Research on Problem Solving:
The Information-Processing Approach
In our description of the history of cognitive psychology in Chapter 1, we noted that
in 1956 there were two important conferences, one at the Massachusetts Institute of
Technology and one at Dartmouth University, that brought together researchers from
many disciplines to discuss new ways to study the mind. At both of these conferences,
Alan Newell and Herbert Simon described their “logic theorist” computer program
that was designed to simulate human problem solving. This marked the beginning ofProblem Jug A Jug BSolution to Problem 1: Desired quantity = B – A – 2CCapacities (cups)Jug CDesired
quantity1 2 3 4 5 6 7 8
21
14
18
9
20
20
15
28127
163
43
42
59
50
39
593
25
10
6
4
3
3
3100
99
5
21
31
24
18
25=
=
B127B106B100B106A21C
3C
3●FIGURE 12.8 Luchins’ (1942) water-jug problem. Each
problem specifi es the capacities of jugs A, B, and C, and a fi nal
desired quantity. The task is to use the jugs to measure out the
fi nal quantity. The solution to problem 1 is shown. All of the other
problems can be solved using the same pattern of pourings,
indicated by the equation, but there are more effi cient ways to
solve 7 and 8. (Source: Based on A. S. Luchins, “Mechanization in Problem
Solving—the Eff ect of Einstellung,” Psychological Monographs, 54 , 6, 195, 1942.)Mental
setNo mental
set100Percent using shorter solution
050●FIGURE 12.9 All of the
participants who began the
Luchins’ water-jug problem with
problem 7 used the shorter
solution (right bar), but less
than a quarter of those who
had established a mental set by
beginning with problem 1 used
the shorter solution to solve
problem 7 (left bar). (Source: Based on
A. S. Luchins, “Mechanization in Problem
Solving—the Eff ect of Einstellung,”
Psychological Monographs, 54, 6, 195, 1942.)Copyright 2011 Cengage Learning. All Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part.