As one would expect from a theory that redefines the definition of intelligence, one of the major criticisms of the theory is that it is ad hoc. The criticism is that Gardner is not expanding the definition of the word "intelligence"; rather, he denies the existence of intelligence, as is traditionally understood, and instead uses the word intelligence whenever other people have traditionally used the word "interest." In this view, it is intellectually dishonest to relabel all of a person's talents as "intelligences". This tactic has been criticised by Robert J. Sternberg (1983, 1991), Eysenck, 1994, and Scarr, 1985. Defenders of the M.I. theory would argue that intelligence has never been rigorously defined, thus inviting new efforts to define it.
Gardner has not settled on a single definition of intelligence. He originally defined intelligence as the ability to solve problems that have value in at least one culture, or as something that a student is interested in. However, he added a disclaimer that he has no fixed definition, and his classification is more of an artistic judgement than fact:
Ultimately, it would certainly be desirable to have an algorithm for the selection of an intelligence, such that any trained researcher could determine whether a candidate intelligence met the appropriate criteria. At present, however, it must be admitted that the selection (or rejection) of a candidate intelligence is reminiscent more of an artistic judgement than of a scientific assessment. (Gardner, Frames of Mind: The Theory of Multiple Intelligences, 1985)
One of the criticisms against M.I. theory is aimed at the underlying ideology. Gardner writes "I balk at the unwarranted assumption that certain human abilities can be arbitrarily singled out as intelligence while others cannot" (Peterson, 1997, p. D2) Critics hold that given this statement, any interest or ability is now redefined as "intelligence"; and adherents of M.I. theory can and do declare that all human beings are equally intelligent. Several logical problems are pointed out:
* Gardner doesn't prove that all people are intelligent. Rather, he states this as his assumption, and redefines the word "intelligence" such that all people are equally intelligent by virtue of his definition.
* Once someone adopts Gardner's position, the entire idea of studying intelligence is meaningless. Any ability is intelligence, thereby reducing the meaning of the word "intelligence" to "interest". In accord with this prediction, Gardner has repeatedly changed his theory; students who show an interest in nature are now deemed to have "Natural intelligence", and students interested in spirituality or religion are now deemed to have "Spiritual intelligence".
* The existence of students with any kind of handicaps proves that even in Gardner's scheme, many people cannot be equally intelligent. Sternberg and Frensch write "it seems strange to describe someone who is tone deaf or physically uncoordinated as unintelligent." In Gardner's system, people not interested in nature have zero natural intelligence, people who are deaf have zero musical intelligence, etc.
A number of articles have surveyed the use of Gardner's ideas in classrooms, and claim that there is no evidence that his ideas work in practice. This article, by Steven A. Stahl, found that most of the previous studies which claimed to show positive results had major flaws.
Among others, Marie Carbo claims that her learning styles work is based on research. [I discuss Carbo because she publishes extensively on her model and is very prominent in the workshop circuit...] But given the overwhelmingly negative findings in the published research, I wondered what she was citing, and about a decade ago, I thought it would be interesting to take a look. Reviewing her articles, I found that out of 17 studies she had cited, only one was published. Fifteen were doctoral dissertations and 13 of these came out of one university—St. John’s University in New York, Carbo’s alma mater. None of these had been in a peer-refereed journal. When I looked closely at the dissertations and other materials, I found that 13 of the 17 studies that supposedly support her claim had to do with learning styles based on something other than modality.
James Traub's article in The New Republic notes that Gardner's system has not been accepted by most academics in intelligence or teaching.
George Miller, the esteemed psychologist credited with discovering the mechanisms by which short term memory operates, wrote in The New York Times Book Review that Gardner's argument boiled down to "hunch and opinion" (p. 20). And Gardner's subsequent work has done very little to shift the balance of opinion. A recent issue of Psychology, Public Policy, and Law devoted to the study of intelligence contained virtually no reference to Gardner's work. Most people who study intelligence view M.I. theory as rhetoric rather than science, and they're divided on the virtues of the rhetoric.
Howard Gardner notes in his text, Changing minds: The art and science of changing our own and other people's minds (2004, p. 196), "As one who has thought intensively about multiple intelligences, I am more aware than most of the defiencies in that theory; yet, I am far from declaring that my own theory has been refuted or that I have adopted a new holistic, unitary, or genetically determined view of the human intellect."
