There are many children who are intelligent but cannot read. We identify some of them as having dyslexia. Indeed, IQ, the popular indication of intelligence, does not predict dyslexia. Many children at all levels of IQ fail to learn to read adequately in spite of getting the same instruction in the classroom as their classmates. That some children with a normal IQ of 100 or better do not learn to read is evidence enough for saying that IQ is not very relevant when explaining or predicting reading disability.
In fact, if we agree with this simple and rather obvious statement, we will go against the practices of hundreds of schools in USA and Canada who receive funding for reading-disabled children. This funding is based on the discrepancy between the IQ and reading ability of children on the grounds that the child’s IQ would predict a reading level that is significantly higher than his/her actual level of reading.
What is wrong with using this discrepancy between IQ and reading as a basis for deciding which child is reading normally and which one has a learning disability? The truth is, as mentioned above, reading disability is found at all levels of IQ. A child with an IQ of 80 is as likely to show up in a reading disability class or clinic as a child whose IQ is 120. The “discrepancy” notion is wrong from another point of view—it assumes that IQ should predict reading when we might just as well assume the opposite, that reading should predict IQ.
IQ tests, such as the Wechsler Intelligence Scale for Children (WISC), are generally used to predict reading. This is so because many of its test items are included in the school curriculum. Therefore, a child who is learning-disabled and is doing poorly in school is likely to do poorly in the IQ test as well. So the chances of predicting reading or learning ability from IQ tests are as good as its reverse.
Is intelligence a general mental ability? The British psychologist Spearman attempted to show that intelligence is general; Cyril Burt (who was greatly influenced by Spearman), and, more recently, Eysenck and Jensen, have all supported the view that there is a common trait of intelligence which runs across much of a person’s behavior. They call this the general or g factor. Thus, if you agree with Spearman, Burt, Eysenck, and Jensen, you believe that foolishness or intelligence can be general traits of the people we know.
However, all of us know that some people have special abilities. A great vocal musician may not be very good at some other skill. (In fact, individuals who are musically gifted are quite different from those who are generally gifted, that is, those with a high level of intelligence.) What can we conclude, then, about general intelligence? It is safe to assume that most people can be graded on a scale of general intelligence from extremely unintelligent to quite bright. However, there are specific skills, for example, the ability to excel in art, music, mathematics, and writing creative literature, which go against the g factor.
Another characteristic of intelligence that psychologists often mention is that it has to do with knowing, cognition, understanding, and thinking. In other words, intelligence is a cognitive activity, as distinct from an affective activity. If we divide human activities into three forms, namely, thinking, feeling, and willing, intelligence would be most closely related to thinking. Therefore, intelligent behavior would include all forms of cognitive behavior such as perceiving, attending, learning, memorizing, and thinking.
What can we say, then, about intelligence being a cognitive activity? Intelligent behavior is certainly identified with the acquisition of knowledge and with actions which are based on our plans and judgments, but at the same time it is intimately connected with our emotions and feelings. Complex human characteristics such as intelligence are determined not by a single gene but by a number of genes arranged in a particular manner.
Therefore, it is very difficult to predict whether or not the child of very intelligent parents will also be highly intelligent. In fact, there is no one-to-one relationship between psychological characteristics and physical characteristics that are inherited through specific genes. The inheritance of intelligence is much more complex and can be proved only in studies that include a large group of people rather than one pair of parents.
Also to be remembered here is the fact that if a characteristic is determined by several millions of genes rather than through one gene, then it is much more open to environmental influences. It is not enough to be bom an intelligent baby; unless the baby is given a chance to have a normal life with good nutrition, good medical care, stimulation at home (people talking to the baby), and, later on, opportunity for good education, the child may not grow up to be an intelligent person.
In fact, millions of children in the world do not get the opportunity to develop their intelligence; millions do not get a chance for education. Who knows how many of them, given adequate healthcare and a chance for good education, would turn out to be talented artists and leading scientists.