Understanding Psychology (10th Ed)

 
Looking
Ahead 
Two very diff erent people with widely diff erent intellectual capabi-
lities and strengths—and yet, at their core, Chris Burke and Sho 
Yano share basic aspects of humanity and even, one could argue, 
intelligence that ultimately make them more similar than diff erent. 
In the following modules, we consider intelligence in all its 
many varieties. Intelligence represents a focal point for psycholo-
gists intent on understanding how people are able to adapt their 
behavior to the environment in which they live. It also represents 
a key aspect of how individuals diff er from one another in the 
way in which they learn about and understand the world. 
We begin by considering the challenges involved in defi ning 
and measuring intelligence. If you are like most people, you 
have probably wondered how smart you are compared with 
others. Psychologists, too, have pondered the nature of intelli-
gence. We examine some of their conceptions of intelligence as 
well as eff orts to develop and use standardized tests as a means 
of measuring intelligence. We also consider the two extremes of 
individual diff erences in intelligence: mental retardation and 
giftedness. Finally, we explore what are probably the two most 
controversial issues surrounding intelligence: the degree to 
which intelligence is infl uenced by heredity and by the environ-
ment and whether traditional tests of intelligence are biased 
toward the dominant cultural groups in society—diffi
cult issues 
that have both psychological and social signifi cance.
feL82795_ch09_276-305.indd Page 278 7/31/10 1:17 PM user-f465
feL82795_ch09_276-305.indd Page 278 7/31/10 1:17 PM user-f465
/Users/user-f465/Desktop
/Users/user-f465/Desktop

---

279
Members of the Trukese tribe in the South Pacifi c often sail a hundred miles in open 
ocean waters. Although their destination may be just a small dot of land less than a mile 
wide, the Trukese are able to navigate precisely toward it without the aid of a compass, 
chronometer, sextant, or any of the other sailing tools that are used by Western naviga-
tors. They are able to sail accurately even when the winds do not allow a direct approach 
to the island and they must take a zigzag course. (Gladwin, 1964; Mytinger, 2001) 
How are the Trukese able to navigate so effectively? If you asked them, they could 
not explain it. They might tell you that they use a process that takes into account the 
rising and setting of the stars and the appearance, sound, and feel of the waves 
against the side of the boat. But at any given moment as they are sailing along, they 
could not identify their position or say why they are doing what they are doing. Nor 
could they explain the navigational theory underlying their sailing technique. 
Some people might say that the inability of the Trukese to explain in Western 
terms how their sailing technique works is a sign of primitive or even unintelligent 
behavior. In fact, if we gave Trukese sailors a Western standardized test of naviga-
tional knowledge and theory or, for that matter, a traditional test of intelligence, they 
might do poorly on it. Yet, as a practical matter, it is not possible to accuse the Trukese 
of being unintelligent: Despite their inability to explain how they do it, they are able 
to navigate successfully through the open ocean waters. 
Trukese navigation points out the diffi culty in coming to grips with what is 
meant by intelligence. To a Westerner, traveling in a straight line along the most 
direct and quickest route by using a sextant and other navigational tools is likely to 
represent the most “intelligent” kind of behavior; in contrast, a zigzag course, based 
on the “feel” of the waves, would not seem very reasonable. To the Trukese, who 
are used to their own system of navigation, however, the 
use of complicated navigational tools might seem so overly 
complex and unnecessary that they might think of Western 
navigators as lacking in intelligence. 
It is clear from this example that the term intelligence can 
take on many different meanings. If, for instance, you lived 
in a remote part of the Australian outback, the way you 
would differentiate between more intelligent and less intel-
ligent people might have to do with successfully mastering 
hunting skills, whereas to someone living in the heart of 
urban Miami, intelligence might be exemplifi ed by being 
“streetwise” or by achieving success in business. 
Each of these conceptions of intelligence is reasonable. 
Each represents an instance in which more intelligent people 
are better able to use the resources of their environment than 
are less intelligent people, a distinction that is presumably 
basic to any defi nition of intelligence. Yet it is also clear that 
these conceptions represent very different views of intelligence. 
That two such different sets of behavior can exemplify 
the same psychological concept has long posed a challenge