Intelligence

A definition of intelligence from the glossary of a psychology text book is, “A complex and controversial concept : Learning ability as contrasted with achievement” (Rathus, 1999).  It is a fairly basic definition.

According to David Wechsler, the originator of the most widely used series of contemporary intelligence tests, the definition of intelligence is the “capacity of an individual to understand the world and the resourcefulness to cope with its challenges” (Wechsler,1975).  To Wechsler, intelligence involves “accurate representation of the world and effective problem solving” (Rathus, 1999).  His definition is one of the most wide open, because it could refer to all kinds of intelligence (practical, academic, emotional, etc.)

Although psychologists and other experts disagree as to what intelligence is, there are many methods of measuring it.  The first test of this kind was the Binet-Simon Scale.  It came in to use in 1905, by the French public school system, and it has changed quite a bit since then.  When Alfred Binet designed this test he decided that his test should have one overall score so it would be easy for the school system to use.  He decided that intelligence must increase with age, so older children should get more answers right.  Then he included a series of age-graded questions, so that younger children would answer easier questions, and older children more difficult questions.  When the children answered questions correctly, they earned “months” of credit.  The more questions answered correctly, the higher the child’s mental age, or MA.

Later, Louis Terman would adapt the test for use with American children.  The first version, the Stanford-Binet Intelligence Scale (SBIS) came out in 1916.  It included more items and was used with children aged 2-16.  Instead of an MA, this test yielded an Intelligence Quotient (IQ).  An IQ was scored by dividing the child’s MA by their true age, then multiplying by 100.  The SBIS is still in use today with people ages two and up (Rathus, 1999).

The Stanford-Binet Intelligence Scale is the original individual intelligence test, but today the Wechsler Scales are more widely used.  The Wechsler scales test individuals on both verbal tasks and performance tasks.  For example a verbal task would be asking a child to define a word.  A performance task would be asking a child to put together pieces of a puzzle in order to form a meaningful object.

The SBIS and the Wechsler are one-on-one tests.  This is still considered the best way to yield an accurate result.  However, large institutions felt the need to test large numbers of people at the same time.  These group tests were developed during World War I, and were administered to over four million children by the year 1921.  At first these tests were widely accepted and “heralded as remarkable instruments.”  Schools used these tests to place students, but as the years went on they were heavily criticized, because some school administrators would rely on these test scores alone.  They would not seek out any other information about the child and it was felt by many that this was not fair, that a person’s abilities, academic capabilities, or worth could not be summed up in a single test.

It is readily apparent that there are many views as to what intelligence really is, and what it means.  Researchers will, no doubt, continue to find areas of debate for years to come.   I believe that the basic underlying application of intelligence study should be to try to understand the mechanisms that help us develop our individual abilities, talents, emotions, and skills; those things that allow us to fully live our lives.  If, through the study of intelligence, better methods of developing individual potential can be discovered, society will benefit greatly.