Intelligence Quotient

Historical Background

Before Alfred Binet (1857–1911) and, to some extent, Francis Galton (1822–1911), gradations of mental worth were generally determined by physiological indices, such as cranial capacity. Galton extended the psychometric assessment of human qualities in many directions, including the assessment of intellect with various response time measures; however, Binet's work had the single most significant impact on the conceptualization of IQ.

Binet was commissioned by the French government to assist with the identification of students who were unlikely to benefit from ordinary schooling and therefore should be offered remedial or special education. Having become quite discontented with the utility of cranial measures, Binet searched for something more definitive. His early ideas for developing a test of intelligence drew heavily from one of his countrymen, Blin, who had developed a series of structured questions that were designed to assess the judgment abilities of the individual.

It is important to note that Binet was very explicit in stating that the scores derived from his tests were rough, that they were not intended for use in ranking normal children, and above all else, they were indicators of current functioning and did not speak to the past or future capabilities of the child. An educator at heart, Binet was a strong believer in cognitive modifiability, a view that suggests that intelligence is not a fixed quantity, but one that can be modified and enhanced. This view tends to sit in stark contradiction with many modern theories of intellectual ability, which suggest that intelligence is an innate and relatively fixed capacity.

As part of his remedial education programs, Binet advocated what he called exercises in “mental orthopaedics.” These were based on the belief that one first needed to learn how to learn. He linked increased academic performance as a function of training to an increase in intelligence. Binet was also concerned that scores on his tests should not be misinterpreted, and he cautioned overzealous teachers against the temptation to use the test results to get rid of unruly or uninterested students.

The Problems of Measuring Intelligence: The Appearance of Mental Age

Binet recognized that when he added up the marks on his scales, the score in and of itself was unable to tell him very much about the ability of the individual. What was needed was some way to compare a child's score with some benchmark. Binet was particularly interested in disentangling native intelligence from the effects of schooling; thus, tests of educational achievement would not serve as an appropriate comparison. Binet recognized that this benchmark needed to be empirical, because he was rightfully cautious[Page 474] about accepting the evaluations of parents and teachers too literally, believing they were susceptible to any number of biases (e.g., the protective parent might exaggerate the capacity of his or her child; a teacher wanting to minimize troubles in his or her classroom may provide an underwhelming evaluation of the child). Furthermore, without some clearly defensible and replicable criterion that could be agreed upon, meaningful assessment of change would not be possible.

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