Introduction Nearly 20 years ago, Howard Gardner mounted a challenge to conventional thinking on the nature of human intelligence with the presentation of a provocative new conception, which was neatly encapsulated in the title of his 1983 book, Frames of mind: The theory of multiple intelligences. In this work, Gardner mapped out an alternative to the prevailing orthodoxy that intelligence in humans is a general intellectual ability or global factor, which permeates all aspects of cognition, and most effectively predicts an individual's performance in school or work contexts, and in many other aspects of well-being in life. As such, this general factor, known as g, which is extracted statistically by means of a technique called factor analysis, is for those involved in mainstream intelligence research and psychometric testing, the working definition of intelligence, and is interchangeable with the more common expression of IQ (Gottfredson, 1998, pp. 24-25). Although not disputing the existence of g, Gardner nevertheless argues that the conventional view of a single general intelligence is far too narrow to be a useful measure of human potential and capability, for it fails to come to grips with higher capacities such as creativity, and is insensitive to a range of socio-cultural roles (Gardner, 1993a, pp. 24, 39). In particular, he charges that the IQ view of intelligence is consistent with the concerns of traditional psychology, and is a `one-dimensional' view of mental ability that focuses principally on logical-mathematical and linguistic reasoning, both of which have corresponded with a conventional view of schooling and mental assessment (see Gardner, 1993b, pp. 5-6, 20-21). In contrast to this view, and as a result of his own work in developmental psychology, Gardner concluded that human intelligence encompasses a much broader, and more universal set of competencies which, as relatively independent faculties of mind, constitute a collection of discrete and more or less autonomous intelligences. These include the traditional logical-mathematical and linguistic forms of intelligence, and some less conventional forms such as musical, spatial, bodily kinesthetic, interpersonal, and intrapersonal intelligences (Gardner, 1993a, pp. 73-78, 1993b, pp. 17-26, 1998). In all, Gardner originally identified seven distinct intelligences, but later added an eighth `naturalist' form of intelligence in 1995, and more recently has been considering a ninth form of `existential' intelligence (Gardner, 1998, p. 21). Gardner's alternative therefore incorporates a pluralistic view of mind and intellect, which recognises many different and discrete facets of cognition, and possible profiles of mental capability and competence. Instead of there being a single dimension of intellect along which individuals can be rank-ordered, there are instead considerable differences in the intellectual strengths and weaknesses of various individuals, and in the ways in which they approach cognitive tasks (Gardner, 1993a, pp. 6, 169-170, 1994, p. 740). In what follows, consideration will be given to some of the central features of Gardner's conception, where attention will focus in particular on a methodological evaluation of the theory's content and structure from within a naturalistic-coherentist framework for the justification of knowledge, in an attempt to discern how well this alternative to the mainstream stands or falls in terms of the explanatory tasks that it sets for itself. Methodological considerations Although the theory of multiple intelligences (MI theory) has generated controversy in psychological quarters, it has nevertheless been more generously received in educational circles, as it has accorded well with educator intuitions that children are intelligent in different ways, and that different educational approaches may reach students more effectively, if favoured ways of learning and knowing are accounted for in the areas of curriculum, instruction, and assessment (Gardner, 1998, p. …