In Gardner's theory, the word intelligence is used in two senses. Intelligence can denote a species-specific characteristic; homo sapiens is that species which can exercise these eight intelligences. Intelligence can also denote an individual difference. While all humans possess the eight intelligences, each person has his/her own particular blend or amalgam of the intelligences.
The following definitions of the intelligences, adapted by White and Blythe (1992), from the originals presented in Frames of Mind, list occupation, professions, disciplines, areas and directions an intelligence can take. But these are by no means the only examples; nor do any of these examples or end states represent the use of any one intelligence to the exclusion of all others. Individuals are never endowed solely with one intelligence. Rather, all brain-unimpaired people possess all the intelligences, which they blend in various ways in the course of creating something that is meaningful or performing a meaningful role or task.
Linguistic intelligence allows individuals to communicate and make sense of the world through language. Poets exemplify this intelligence in its mature form. Students who enjoy playing with rhymes, who pun, who always have a story to tell, who quickly acquire other languages--including sign language--all exhibit linguistic intelligence.
Musical intelligence allows people to create, communicate, and understand meanings made out of sound. While composers and instrumentalists clearly exhibit this intelligence, so do the students who seem particularly attracted by the birds singing outside the classroom window or who constantly tap out intricate rhythms on the desk with their pencils.
Logical-mathematical intelligence enables individuals to use and appreciate abstract relations. Scientists, mathematicians, and philosophers all rely on this intelligence. So do the students who "live" baseball statistics or who carefully analyze the components of problems--either personal or school-related--before systematically testing solutions.
Spatial intelligence makes it possible for people to perceive visual or spatial information, to transform this information, and to recreate visual images from memory. Well-developed spatial capacities are needed for the work of architects, sculptors, and engineers. The students who turn first to the graphs, charts, and pictures in their textbooks, who like to "web" their ideas before writing a paper, and who fill the blank space around their notes with intricate patterns are also using their spatial intelligence. While usually tied to the visual modality, spatial intelligence can also be exercised to a high level by individuals who are visually impaired.
Bodily-kinesthetic intelligence allows individuals to use all or part of the body to create products or solve problems. Athletes, surgeons, dancers, choreographers, and crafts people all use bodily-kinesthetic intelligence. The capacity is also evident in students who relish gym class and school dances, who prefer to carry out class projects by making models rather than writing reports, and who toss crumbled paper with frequency and accuracy into wastebaskets across the room.
Interpersonal intelligence enables individuals to recognize and make distinctions about others' feelings and intentions. Teachers, parents, politicians, psychologists and salespeople rely on interpersonal intelligence. Students exhibit this intelligence when they thrive on small-group work, when they notice and react to the moods of their friends and classmates, and when they tactfully convince the teacher of their need for extra time to complete the homework assignment.
Intrapersonal intelligence helps individuals to distinguish among their own feelings, to build accurate mental models of themselves, and to draw on these models to make decisions about their lives. Although it is difficult to assess who has this capacity and to what degree, evidence can be sought in students' uses of their other intelligences--how well they seem to be capitalizing on their strengths, how cognizant they are of their weaknesses, and how thoughtful they are about the decisions and choices they make.
Naturalist intelligence allows people to distinguish among, classify, and use features of the environment. Farmers, gardeners, botanists, geologists, florists, and archaeologists all exhibit this intelligence, as do students who can name and describe the features of every make of car around them.
In a recent article, "Are there additional intelligences?" Gardner examined two more candidate intelligences, naturalist, and spiritual, but ended up rejecting spiritual--at least for now--because it does not meet the eight criteria named earlier. He is still amassing evidence for other suggested intelligences. For example, existential intelligence--manifest in somebody who is concerned with fundamental questions of existence--does not, as yet, seem to meet all criteria. If decisions about intelligences are to be taken seriously, Gardner believes, they must depend upon examination of the available data. So at this point, one might say that the existential intelligence is the "half" in the 8-1/2 intelligences.