• The history of hypertext: the memex

The 'memex' was a project of the 1940s, in which information in all fields would be stored so as to be interrelated: this was a new approach to knowledge. Later hypertext programmes of the 1980s partly implemented such a principle, having eventually developed the necessary technology.

• Diagrams

Diagrams (which we started studying as a means of establishing correlations) relate concepts to their context

The relations between concepts can be expressed as multidimensional diagrams, developed with computer programmes: 'fisheye views' (1981) stressing 'focus + context' relations betweeen concepts