Principle of causality is fundamental to human thinking, and it has been observed experimentally that this assumption leads to complex hypothesis for… - Brian R. Gaines

Models of human reasoning are clearly relevant to a wide variety of subject areas such as sociology, economics, psychology, artificial intelligence and man-machine systems. Broadly there are two types: psychological models of what people actually do; and formal models of what logicians and philosophers feel a rational individual would, or should, do. The main problem with the former is that it is extremely difficult to monitor thought processes - the behaviourist approach is perhaps reasonable with rats but a ridiculously inadequate source of data on man - the introspectionist approach is far more successful [e.g. in analysing human chess strategy... but the data obtained is still incomplete and may not reflect the actual thought processes involved.

The motivation for an "information highway" was expressed in 1937, just prior to the advent of computer technology, when Wells was promoting the concept of a "World Brain" based on a "permanent world encyclopaedia" as a social good through giving universal access to all of human knowledge. He remarks: <blockquote> "our contemporary encyclopaedias are still in the coach-and-horses phase of development, rather than in the phase of the automobile and the aeroplane. Encyclopaedic enterprise has not kept pace with material progress. These observers realize that the modern facilities of transport, radio, photographic reproduction and so forth are rendering practicable a much more fully succinct and accessible assembly of facts and ideas than was ever possible before." (Wells, 1938) </blockquote>

Bush, a technical advisor to Roosevelt, published in 1945 an article in Atlantic Monthly which highlighted problems in the growth of knowledge, and proposed a technological solution based on his concept of memex, a multimedia personal computer: <blockquote> "Professionally, our methods of transmitting and reviewing the results of research are generations old and by now are totally inadequate for their purpose...The difficulty seems to be not so much that we publish unduly in view of the extent and variety of present-day interests, but rather that publication has been extended far beyond our present ability to make real use of the record." (Bush, 1945) </blockquote> The world brain has continued for over fifty years to provide an active objective for the information systems community (Goodman, 1987), and memex is often quoted as having been realized fifty years later through the World Wide Web (Berners-Lee, Cailliau, Luotonen, Nielsen and Secret, 1994).