Is intelligence best described as a single entity, or as more than one thing? If the latter, how many “intelligences” are there?
It is important to note that this question of single or multiple intelligences is not a new one. Many psychologists and scientists have tried for centuries to define the term “intelligence” in a scientifically correct and acceptable manner. It is apparent that many, who have aspired, have arrived at controversial theories that have provoked international debate. The most prevalent theories are those of Spearman’s General Intelligence (1904) and the contemporary Multiple Intelligence theories of Gardner (1983) and Sternberg (1999). Although these theorists maintain divergent ideas, one might be inclined to observe intelligence as Wechsler (1939) did- as a combination of the single and multiple theories.
The question is often asked: Why is it that there is a general trend for individuals who are good at one thing to be good at others? Teachers sometimes refer to this tendency as correlation not compensation (Kline, 1991, p3). Charles Spearman wanted to know why human abilities were positively correlated. In 1904, he published an article in the American Journal of Psychology to examine the basic function he termed “General Intelligence”. His aims were to verify it in a specific objective method and to discover accurate means of measuring it (Spearman, 1904, p11). He concluded that a correlation did exist and that it could be attributed to general intelligence or little g. It seemed “g” was universal to all tasks that necessitated ability, hence the correlation. For example: Ability at Latin, required g and a definite Latin factor; mathematics depended on g and a mathematics factor, and so on. Spearman had achieved the invention of a statistical method (factor analysis) which could uncover these structures of ability.
However, his theory of single or general intelligence was bound to cause controversy. One of Spearman’s earliest opponents was L.L. Thurstone (1959). By attempting to disprove g, he administered 56 different tests to individuals and identified 7 different clusters (Myers, 2007, p432). His data was subsequently analyzed, and investigators found that a there was a tendency for people who did well in some clusters, to do well in others. Thurstone had in fact provided evidence of g. Interestingly enough, almost 50 years later, Wendy Johnson and Thomas Bouchar (2005) tried disproving g by administering 42 diverse tests of mental ability to 436 adult. Again, evidence of correlation attributed to g was discovered.
Psychometricians have adopted and adapted Spearman’s theory and an improved form of factor analysis is used extensively in today’s fields of research.
Yet, after replication and further investigation, even Spearman had to admit something in addition to g was assisting in producing correlations. This something was an unusual, additional component in different groups of tests which Spearman recognized as a “group” factor (Guildford, 1967, p56). Although he recognized them, he still did not give much credibility to group factors. Interestingly, the group factors he identified and psychologically interpreted are remarkably similar to today’s multiple factors.
In opposition to the general intelligence theory, Howard Gardner (1999) proposed a theory of multiple intelligences. His aim was to define the concept of intelligence more accurately and to investigate whether the current methods of measuring intelligence, were in fact, scientific. Gardner’s theory was aired in his 1983 book,Frames of Mind: The Theory of Multiple Intelligences. In his book he claims that each person has noticeably varying levels of different intelligences and that each person has a unique “cognitive profile.” He originally suggested 7 “abilities” or intelligences but after further refining in subsequent years, is accredited with identifying the following 8 intelligences: linguistic, logical-mathematical, musical, spatial, bodily-kinesthetic, interpersonal, and intrapersonal (Gardner, 1983). Currently, Gardner is in the process of identifying his ninth intelligence, namely spiritual/existential intelligence (Gardner 1999).
Critics of Gardner have pointed out that without test that can accurately measure all these different intelligences it will forever be impossible to verify his theory. It is also suggested that these “intelligences” are not intelligences but abilities (Myers, 2007, p435). Also, for example: If athletic ability is a bodily-kinestic intelligence- then will someone with physical defects be mentally retarded as well? http://www.howardgardner.com/FAQ (2009)
Yet, although Gardner stands firmly behind his theory, he is open to the possibility of rapprochement between multiple intelligence and other contending theories.
The most recent and popular of these competitors, is the “triarchic” model put forth by Robert Sternberg. He proposes three different facets of intelligence-which he labels as the componential, the experiential, and the contextual (Sternberg 1999). He has also gone on to devise various measures for each. Alongside his triarch theory, Sternberg has been working on another form of intelligence he describes as successful intelligence (Sternberg, 2002).
Critics of Sternberg’s theory argue that his three intelligences are not as distinct as he thinks and that they might in fact share an underlying general intelligence (Brody, 2003). His ideas have repeatedly been criticized in the scientific literature for lacking empirical support (e.g., Deary, 2001; Gottfredson, 2003; Jensen, 1998).
Other’s theories of multiple intelligence claim the existence of social or emotional intelligence. As with Sternberg’s successful intelligence, there are numerous theories of other intelligences, yet unproven. This makes it difficult to answer the question: How many intelligences are there? Various and extensive tests have been developed to distinguish different intelligences from one another, yet they still only measure what we intend for them to.
Undisputedly, the most popular and accurate form of intelligence testing is that of David Wechsler. By combining the concept of single and multiple intelligences, he separated the concept ofintelligenceinto two main areas: verbal and performance or non-verbal areas. Each is further subdivided and tested with a different subtest. Prominent differences among these scores will alert the test administrator to the possibility of a learning difficulty or brain disorder (Myers, 2007).
It is interesting to keep an eye on the neuroscientific research being done on this topic. Brain imaging research using PET, fMRI, and EEG data are helping to establish the functional neuroanatomy ofgeneral intelligence (Haier,White and Alkire, 2003). If in fact, general intelligence were to be proven beyond reasonable doubt, it will irrefutably change the way we view intelligence.
The different theories of intelligence are arguably interesting and deserving of appreciation. It is noticeable that no one really has a definitive definition or proven theory. Spearman’s general intelligence theory, although controversial, has been around for over 100 years and is still not disproven. The multiple intelligence theories of Gardner and Sternberg are being incorporated in educational settings and providing teachers with more productive teaching tools. The combi theory of Wecshler is possibly the most comprehensive and relevant to our modern day application of what we presume intelligence to be. It neither refutes a single intelligence nor claims it to be the only intelligence. It allows room for other abilities to be measured even though we currently have no precise number of intelligences. Perhaps, the further development of neuroscientific study just might give us a clearer idea of how the various or single intelligence(s) actually work.
Gardner, H. (1983). Frames of Mind: The Theory of Multiple Intelligences. New York: Basic Books
Gardner, H. (1999) Intelligence Reframed. New York: Basic Books
Gardner, H. (2003) Frequently Asked Questions of Howard Gardner. http://www.howardgardner.com/FAQ. [Accessed 23rd October 2009]
Gottfredson, L. (2003). Dissecting Practical Intelligence Theory: Its claims and Evidence. Intelligence. 31. 343-397.
Guilford, J.P. (1967). The Nature of Human Intelligence. United States of America: McGraw-Hill.
Haier,White & Alkire (2003). Individual differences ingeneral intelligencecorrelate with brain function during nonreasoning tasks. Intelligence. 31. 429-441
Kline, P. (1991). Intelligence: The Psychometric View. Kent: Routledge
Myers, D.G. (2007). Psychology. (8th ed). New York: Worth.
Spearman, C. (1904) General Intelligence: Objectively Determined and Measured. American Journal of Psychology. 15. 201-293.
Sternberg, R. (1999). A Triarchic Analysis of an Aptitude-Treatment Interaction. European Journal of Psychological Assessment. 15. 1-3.
Sternberg, R. (2002). Intelligenceis not just Inside the Head: The Theory ofSuccessful Intelligence. Improving Academic Achievement. 227-244.