“An earlier paper (Pask, 1976) introduced conversational techniques, some involving a human participant in dialogue with a student, others involving a mechanically or computer implemented 'participant' through which the student 'talks to himself' under restrictions imposed by the device. In either case (human or mechanical monitoring) the subject matter of a conversation is represented in a liberally conceived, but standard, fashion, as a conversational domain consisting in an entailment structure (embodying one or more description schemes and indicating the many ways in which one topic may be known in terms of or derived from others) and behaviour graphs (one for each topic in the domain) that prescribe what may be done to model or explain the topic in question. Within this framework, the conversational techniques secure, or approximate, a standard condition for experiments on learning.”

Source: Styles and Strategies of Learning (1976), p. 128: Pask is referring to the article: Pasc, G. (1976). "Conversational techniques in the study and practice of education". In: British Journal of educational Psycholy, Vol 46, p. 12-25.