Some schools have based their entire curriculum around it while others have rejected it completely. There are many educators who agree in part but cannot accept the whole theory in its entirety. Whatever the reaction, Howard Gardner's theory of multiple intelligences has impacted thinking and practice in education.

Devised in 1983 by Howard Gardner, an American developmental psychologist, the theory of multiple intelligences is already over 30 years old. In his book Frames of Mind, Gardner wrote ‘an intelligence is the ability to solve problems, or to create products, that are valued within one or more cultural settings.’ Gardener’s theory takes issue with the traditional Intelligence Quotient - commonly referred to as IQ - test which infers that intelligence is a single entity which can be defined by a single measure based on short answers to a variety of questions. This test measures only two intelligences, verbal and computational.

There are eight intelligences rather than two, according to Gardner. The first two are verbal-linguistic and mathematical-logical and these are the two that are primarily assessed in traditional tests as well as being the most valued in the mainstream educational system. The next three are musical intelligence, visual-spatial intelligence, or the ability to create and manipulate mental images, and bodily-kinaesthetic intelligence which involves factors such as coordination, balance, speed and strength. The final two intelligences on the original list of seven were interpersonal and intrapersonal intelligences. The former refers to the capacity of understanding the motivations, intentions and desires of other people while the latter refers to the ability to understand oneself. The eighth intelligence which was added later is naturalist intelligence - the ability to discriminate and use features of the environment.

These intelligences are not independent of one another but rather are employed in varying combinations to solve problems or create products or services that are of use. Gardner considers that each person is unique in the combination of intelligences, just as each person’s fingerprint is unique. The original concept of intelligence assumes that it is inherited and therefore not much could be done if one were not good at maths or not talented at music. Gardner argues that everyone has multiple intelligences which can be strengthened through nurturing or weakened through lack of use or practice. He maintains that there is a biological and a cultural basis to intelligence. Biological because each intelligence is anatomically separate, as is evident when there is damage to the brain and one characteristic is affected but others are not; and cultural in that some cultures prize certain abilities over others and so those intelligences will develop to a larger extent than in cultures that do not appreciate them.

Gardner is often criticised for simply describing a set of talents or skills and for having no empirical or research evidence for his list. However, in order to be classified as an intelligence, there were eight criteria that needed to be fulfilled. If any one of the eight was not met, the characteristic being considered was discarded. The theory of multiple intelligences has not been widely accepted by academia as they consider it to be unscientific due to the inadequacy of the criteria he used to define intelligence. Gardner himself admits that some of the judgements he made were more subjective than not. Other arguments against the theory are that some of the intelligences, such as musical and visual-spatial, are talents more than anything else. The difference between an intelligence and a talent is that the former needs to adapt to the demands of everyday life whereas the latter does not.

The theory of multiple intelligences, however, has more fans than critics. This is particularly true in the field of education where many educators had already understood that students have different approaches to learning and just because one does not do so well in one area does not mean they cannot excel in others. Many schools are incorporating Gardner's theory and making changes to their curricula to include the different styles of learning. Students who had previously been isolated by the traditional emphasis on maths and language are achieving success either because a different approach to teaching has been adopted or because there is a new appreciation of different types of intelligence.

The theory of multiple intelligences may not be flawless as Gardner himself admits, but the impact it has had on developmental psychology and education has been a major one. The fostering of the unique blend of intelligences that define each person can only be of advantage to that individual, his family, the society he or she lives in and to the world in general.