Bernstein (1999) distinguishes between what he refers to as vertical and horizontal discourses. He defines a vertical discourse as follows:‘a vertical discourse takes the form of a coherent, explicit, and systematically principled structure, hierarchically organised, as in the sciences, or it takes the form of a series of specialised modes of interrogation and specialised criteria for the production and circulation of texts, as in the social sciences and humanities’(Bernstein 1999: 159). In contrast:‘a horizontal discourse entails a set of strategies which are local, segmentally organised, context specific and dependent, for maximising encounters with persons and habits’(Bernstein 1999: 159). In addition to vertical and horizontal discourses, Bernstein also characterizes vertical discourses as having either hierarchical knowledge structures (the physical sciences) or horizontal knowledge structures (the humanities and social sciences)(Bernstein 1999: 162). Bernstein represents a hierarchical knowledge structure as a triangle:

And he states:‘This form of knowledge attempts to create very general propositions and theories, which integrate knowledge at lower levels, and in this way shows underlying uniformities across an expanding of apparently different phenomena. Hierarchical knowledge structures appear, by their users, to be motivated towards greater and greater integrating propositions, operating at more and more abstract levels. Thus, it could be said that hierarchical knowledge structures are produced by an “integrating” code’(Bernstein 1999: 162). In contrast Bernstein (1999: 162) describes horizontal knowledge structures as consisting of ‘a series of specialised languages with specialised modes of interrogation and criteria for the construction of specialised texts. Thus, any one of the specialised disciplines within the form of a horizontal knowledge structure found within the humanities can be visually portrayed as: L1 L2 L3 L4 L5 L6 L7... Ln’(Bernstein 1999: 162). To continue the quote: