We usually consider media as mediating between people. However, they can also be considered as mediating, within each person, between the subjective map and the objective world. The subjective map could be considered as composed of a perceptual map and a conceptual map, corresponding roughly to the thing and the word in the objective world and to text- and image-based media. [see Figure 2]. It is a useful metaphor to consider the perceptual map as a function of the right hemisphere and the conceptual map as a function of the left hemisphere. Within this metaphor, the computer could be consider as the corpus callosum. This captures the two basic characteristics of computer-based media - integration and interactivity. The corpus callosum links the two hemispheres, as the computer integrates text and image, and it links the cerebral cortex with the rest of the body, as the computer provides interactivity between thought and action.

      Now that we finally have a medium which represents the whole nervous system, a positive prosthetic which fits, a three-dimensional tool which mediates between our three-dimensional brain and our three-dimensional world, we have to reconsider our current dependence on one- and two-dimensional tools, and our continuing use of the computer as a box to bury old one- and two-dimensional media. We typically use the computer as a typewriter to do one-dimensional word-processing. It is necessary to proceed to two-dimensional idea-processing, in which the computer is used to generate the hierarchical structure of thought underlying the sequential presentation of language, and to three-dimensional multimedia, in which it is used to nest more nodes within any node and to link any two nodes within the hierarchy [see Figure 3]. This three-dimensional structure is isomorphic with the cognitive structure of the subjective map, viewed as concepts with relationships between them, and with the informatics infrastructure of the objective world, viewed as computers interlinked with telecommunications [see Figure 4].

      1  2  3  4  5  6  7  8  9  10  11  12