"A retrieval system can be studied at three levels:"

“There does seem to be among some members of our profession a rather desperate search for a "fundamental theory of information", which leads them to attempt to derive our practice from disciplines such as epistemology, or hermeneutics, or discourse analysis, or semiotics, or even "cybersemiotics". Their derivations rarely make adequate contact with the realities of information practice … The theory of a science should spring from deep immersion in its practice.”

“The areas traditionally concerned with such systems are: publishing in all its ramification, librarianship, bibliography, documentation, record management, archives and the like. Systematic study of the activities in all these areas has lead to increased recognition of their common features. They are all concerned with information systems, and their study may include in the wider field of 'information science and technology' or 'informatics' .”

“Information practice... consists of two activities that we may call diagnosis and prevention. Diagnosis is identifying what is the most probable information need of a user in a particular state of information want. Provision is deciding what action is most likely to meet that need. Information science seeks to understand the potential range of user situations giving rise to information want and needs; to develop methods of identifying the actual information needed; to understand and expand the range of possible ways of satisfying information need; and to develop methods of deciding what way is most likely to be effective in a particular case.”

“The term “information science” first appeared in the guise of “information scientist”. Particularly in industry during recent decades, some qualified scientists moved out of research, development of production into a new occupational role, that of providing an active information service to their colleagues. They regarded themselves as “information” scientists rather than “research” scientists. As this kind of work expanded and became formalized the need was seen to provide training for those who would enter the occupation. In time, the content of this training came to be called 'information science'.”

“Bertie Brookes and I shared a common view that, beyond the practical activities of information provision, there could be discerned a more general science of information. He tended towards a mathematical formulation of this: I was more interested in its social aspects.”

“An information system is an organisation of people, materials and machines that serves to facilitate the transfer of information from one person to another. Its function is social: to aid human communication. If we take this to mean all reception of signals by the human senses - then communication is an incessant and essential accompaniment of all human activity. If we restrict the meaning of signals to flowing between people, much of the daily life of most of us is occupied by such interpersonal acts.”