During the late 1880s Binet studied the behaviour of his daughters. He also tried new psychological tests on them. Some tests were about reaction time and sensory discrimination. He discovered that his daughters, without developed intellect, it did about as well as adults. He did not think the measurements were good indicators of intelligence. He wanted tests that were about higher and more complex functions, such as language and abstract reason. He was not the only pioneer in testing intelligence, Piaget did this too. He discovered that children have no concept of ​​objects as stable and permanent, and as separate from yourself and your perception. The hypothesis the result is that the intelligence of a child is not is less than that of an adult, but qualitatively different is. There are different development stages.

What did the life and career of Binet look like?

Alfred Binet (1857-1911) was born in France. Binet graduated in law but then went to the medical school. However, he did not like this either. He read a lot of books in the library of Paris at the age of 22. He discovered books about experimental psychology and was instantly inspired by this. In 1880, he had his first scientific publication. He also became enthusiastic about the association psychology of John Stuart Mill. According to Binet, intelligence also works through the law of association. Then Binet became Charcot's assistant, and this remained the case for over a year. He published three books and more than 20 articles on various topics.

Eventually Binet found out that he had had too much faith in Charcot's name and prestige and had not been critical enough. Binet began to do experiments with his daughters at home. He was very aware of the individuality of everyone's intelligence. Deeply impressed by the individuality of man, he decided to work with his colleague Victor Henri in 1895 to set up a program that they called individual psychology (not too confuse with Alfred Adler's approach). They were looking for a series of short tests that would take less than 2 hours and could be carried out with each person. With the help of such tests, one was able to obtain as much information as you could with years of observations and interviews. 

Binet anticipated many projective tests. He was looking for a combination of several long-term tests that could serve as a replacement for the extensive case study, but unfortunately he did not find it. He had confirmed his conviction with the help of the direct testing that the higher, complex mental functions, the significant intellectual differences could be measured.

Together with Theodore Simon (1873-1961) Binet decided to develop a test with which children with a mental handicap, who therefore could not keep up with regular education, could be identified (also called 'feebie-minded' people). Binet and Simon began identifying groups of children who had previously been taught by their teacher or teacher were diagnosed as normal or sub-normal, and then proceeded to test them in different specific ways. They avoided tests with a lot of reading, writing and other school related skills, simply to avoid  that a lack of intelligence was confused with a lack of education. 

In the beginning, a difference in performance was found between both groups, but no perfectly discriminating item was found. Binet and Simon they became frustrated until they realized that they also had to take age into account. Normal and sub-normal children might have passed the tests, but normal children should be able to do this at a younger age. By following this insight, the sub- normal children finally described as being "delayed" mentally. This idea ensured that Binet and Simon were able to develop the first intelligence test in 1905, which also worked. The first item tested whether participants could follow a light with their eyes, to show they could pay attention. Then the children had to grab a small object, eat a candy, shake hands with the researcher and meet a number of requests. Normal children could already do these things at the age of 2, but the most mentally delayed children never quite succeeded to do these things.

What were the successors of the 1905 test?

The 1905 test caused a turning point in the history of psychology, because it distinguished between the different intelligence levels. However, people were more focused on the mentally retarded children, while the most difficult education decisions were more with the older children who were closer to the "normal" line. When adjusting of the test, Binet and Simon ensured that the items were designed according to age, and that,  according to a sample, normal children could have passed the test at the first attempt. For example, an at a level of a six-year-old the test could be performed by a small group normal five-year-olds, half of the six-year-olds and the majority of older children. 

The version from 1908 consisted of 58 items for ages between 3 and 13 years; the version from 1911 consisted of five questions for ages between 5 and 15 years, and five questions for the adult category. With age-standard items, Binet had created a scale with which he was able to provide a single score or intellectual level for each child participating in the test. The questions were always set according to an increasing degree of difficulty. After taking the test, it was possible for the intellectual level to be calculated. 

An example of such a calculation is: a child answers all questions of the level of a seven-year, four questions at the level of one eight-year and two questions at the level of a nine-year-old and therefore has an intellectual level of an 8.2-year-old. In comparing mental sub normality, Binet compared it intellectual level of the child with the actual age. 

He came up with the rule of thumb that children with intellectual levels who were more than two years behind their own age, needed special education. However, Binet was careful with his rule of thumb. He still denied the skill of numbers to accurately summarize a complex quality and he emphasized that different children can reach an identical intellectual level through different patterns of answer specific questions correctly. He also noted that no score is valid for a poorly motivated child, or for children from a different culture than the culture that was used to standardize the questions. 

Binet also believed that intelligence, which was measured through his test, was not a fixed quantity, but something that naturally grows with time, and that can also increase through training (except for mentally retarded children). He developed a program that he called mental orthopaedia, which consisted of various exercises. Children who were limited by an inability to sit still or concentrate, knew by using this program to increase their intellectual level and behaviour.

Binet died of a stroke in 1911 and left behind the basic technology to the modern intelligence tests. Despite the fact that many psychologists still hope to find a yardstick to be culture-independent, innate and close to neurophysiological functions, in order to measure intelligence, the current practical tests depend on similar items like Binet's. Often it is still questions about the high and complex functions such as memory, reasoning, verbal skills and practical judgments. Despite the fact that Binet would have been satisfied with the content of modern intelligence keys, he would have had doubts about other developments regarding the tests.

What is the definition of intelligence?

To start with: the definition of intelligence. Binet had a flexible and pragmatic definition of intelligence and saw it as a collection of separate skills for it memory, attention and reasoning. Charles Spearman (1863-1945) was a supporter of the general intelligence theory("g"). 

Spearman saw that when there is a correlation between different items calculated, they almost always correlated positively with each other. For example, when people are able to get a good score on a vocabulary test, they also tend to score high on arithmetical problems. Furthermore, he discovered that even though most of the tests were positively correlated, some tests had a higher correlation with each other than others. To explain these findings, Spearman came up with the theory that there was a single "factor" where all the other items were to fall under. He gave this factor the name "general intelligence". He also felt that each individual item had an opportunity to specify, so a s-factor. He called this theory the two-factor theory of intelligence. 

Spearman compared the "g" with a supply of mental energy, capable of some specific neurological skills to manage systems or to perform specific tasks. Theoretically, the performance of an individual on a task a collaboration between the available energy (or "g") and the efficiency of a particular "s" involved. The hierarchical nature of correlations suggests that some tasks are more dependent on the "g" and less on the "s". 

Binet believed that different levels of intelligence cannot be approximated in an accurate way, at least not by numbers. Spearman's theory previously suggested that with the "g" level, or "general mental energy", the most important thing is to know about the intelligence of a person. William Stern came with the intelligence quotient. Stern had worried about the fact that the difference between the real age of the child and the intellectual level tested (or the mental age) often increased with time. Binet 's suggestion for a two - year difference between the chronological age and mental age as a symptom of sub-normality was suspicious because it was a different standard for different age groups. The age differences of children increased as they got older, increasing the chances that a diagnosis of sub-normality could occur more often at an older age. 

To solve this inequality, Stern suggested to adjust the ratio of mental age to the chronological age (this ratio he called "intelligence quotient" which he calculated by the mental age divided by the real age). For instance, there could be a child of 5 with a mental age of 4 and a child of 10 with a mental age of 8, that have the same intelligence quotient (0.80). So this took into account the growing differences. Binet would not have been happy with this solution: he had complained about it different patterns of specific answers could produce the same mental age but Stern was able to simplify the problem by passing the same intelligence quotient different combinations of mental and chronological ages could be produced. For other psychologists, simplifying the results through the intelligence quotient was a positive point, because it could now be interpreted more easily.

What did Goddard write about weakness and giftedness?

Henry Goddard (1866-1957) was interested in how different levels of intellectual sub-normality can be accurately diagnosed and so he translated the Binet tests to English. Goddard thought that mental infirmity was a disease-like condition was caused by a defective gene, which turned out to be wrong. But to Goddard, the easiest way to prevent a kind of infirmity epidemic, was to prevent it mentally retarded from even having children. 

He was concerned with negative eugenics: and so mentally retarded people were not allowed to reproduce. They had to stay in institutions under supervision. Some other believers were less… nice when it came to this prevention, however, and forced sterilization. Goddard was hit by his new research into juvenile delinquents and became convinced that environment also played a major role.

The second psychologist who brought out the prominence of Binet's tests in the US was Lewis M. Terman (1877-1956). Terman was one of the first to comment on the usability of the Binet tests in diagnosing superior intelligence. His interest was in children with higher IQ than the average. After an intensive study of gifted children, he discovered that high IQ alone was not a good predictor for intellectual success and that intelligence tests be more suitable for diagnosing lower levels of intelligence anyway, so for what they were originally intended for. The adjustments of the Binet test are therefore applied to the population, often summarized as an IQ. The interpretation of the IQ differs. Some see the score as one variable that is mainly determined by environment and education and not by heredity. 

David Wechsler (1896-1981) was a psychologist in a hospital in New York. He became aware of the need for a better test than the Stanford Binet for the intellectual qualities of the adult population: one with a more sensitive distribution of one's intelligence than a single bad IQ score. His research led to the Wechsler Adult Intelligence Scale (WAIS). This is, up to now, the golden standard for measuring the intelligence of adults. In this test distinguished between verbal and performance IQ. Both this test and the Binet test are often revised, and the scores are often re-standardized in new populations. 

James Flynn discovered in 1984 the Flynn effect. This refers to the fact that people have become increasingly smarter (measured with intelligence tests), about 3 IQ points per decade. This is not possible to explain with genetics so it will have to do with the environment or culture. Developments in radio, television and technology has greatly increased the accessibility and amount of information available.

Who was Jean Piaget (1896-1980)?

Piaget was more concerned with the qualitative intellectual developments. He found evidence that older children do not only think more quickly or more than the younger ones, but also that they think differently a whole. They use cognitive skills and structures that help them to better understand some problems and concepts. So intelligence develops qualitatively with age. 

Piaget came up with the term genetic epistemology, to be able to describe his system of how the mind develops. Together with his colleagues he discovered increasing development phases, or systematic and qualitative differences in the way in which the younger and older children conceptualise tasks and deal with it. Piaget suggested the existence of four ascending stages between childhood and later adolescence. New cognitive skills and strategies develop at every stage, that make it possible to solve problems that the children could not solve at a younger age.

Sensory motor phase (birth up to 2 years): the intelligence of a child exists at this stage mainly from sensory and motor activities. Abstract thinking is not yet possible. The child must achieve object stability - the knowledge that objects remain, even if they are on one specific moment not visible. After they learn that objects exist independently of the environment, it becomes possible to name objects. Gradually they also learn to get more control their own body and environment.

Pre-operational phase (2 to 7 years): children are already aware that objects remain existence, even if they are not visible. However, they do not yet understand much about the properties of objects such as quantity or weight. When water is first in a bottle, and after that being poured into a bowl, the child does not know that the amount of water remains the same although the physical appearance has changed. This is called the conservation of quantity.

Specific operational phase (7 to 11 or 12 years): the conservation problems can now be resolved but not using different solutions. Not all conceptual and reasoning problems can be solved.

Formal operational phase (11 or 12 years): inductive reasoning becomes possible.

Piaget's ideas have been applied in educational settings. He gave the advice that schools could improve by always giving students problems and challenges that best suit their stage of intellectual development. 

Someone who did not agree with him was Lev Vygotsky (1896-1934). He had a socio-cultural perspective on developmental psychology. According to him, everything that happened had the order that the mental development of a child occurs first on a social level before it can become internalized. He promoted the concept of a zone of proximal development (zpd), to indicate the difference between what a person can do intellectually without help, and what he can do with the help from a more skilled person. He therefore saw intelligence as a social characteristic, with sources in the development of language. According to him, intelligence is also about someone's potential to be able to quickly improve with the help of a teacher. Qualities of a teacher are therefore also important. Piaget believed that intellectual development used to be associated with biological and social development. Intellectual growth in a child could be nurtured, just like physical growth, but it was not possible to be accelerated because it is limited. The exact nature of the limitations, the extent to which children can be helped through the development stages and the desirability of it to be accelerated through the stages are important topics. The first to deal with this loved was Jerome Bruner (1915). He came up with the "theory of instruction". According to this theory is the ideal technique to learn new material, by the student through the three ways (modes) of representation of the material, parallel to the cognitive development phases of Piaget. The student starts with the "active mode", where he just goes doing something. Then the child concentrates on the perceptual qualities ("the iconic mode "), before it changes to abstract qualities in symbolic fashion. The child learns during the sensory-motor phase to use the active representation during the pre- operational phase the iconic fashion and during the symbolic operational phase.

ExamTips

• How are Binet's tests still relavant today?
• Why is it, psychologically, so important to us as humans to understand intelligence?