The consistency in the organization of main classes
is the principal feature of Bliss' system. The order of
classes reflects the principle of gradation by specialities
suggested by Auguste Comte (1830-1842) for the
sciences organization: special fields must follow fundamental
sciences, from which they derive. The system
of sciences and special fields was based on what
Bliss considered to be the natural and logical order, the
"system of the nature," that is reality and its various
forms, including human conceptual activities. In Bliss'
opinion, interconnected disciplines and established
continuity among scientific fields would ensure the
realization of an effective encyclopaedia of knowledge,
fully functional to scientific research.
Besides. Bliss founded the division of sciences on
what he defined the principle of "scientific and educational
consensus," that is the scientists agreement
on the order and relationships among sciences. This
order is reflected in turn on the pedagogical order of
fundamental sciences taught in Universities, which
guarantees the stability of the system.
Bliss' attention to the "scientific consensus" can
be related to the theory of domain analysis recently
drawn by Birger Hjorland (2002), who has suggested
considering different fields of knowledge as different
"discourse communities" within the society. Each
community, in fact, has peculiar languages and forms
of communication, specific information systems, citing
methods and criteria to establish document's
relevance; each community pursues its own objectives,
uses peculiar intercommunication tools among
members, and uses a specialized terminology. Unlike
Bliss' orientation, theory of domain analysis takes
into account that different knowledge fields can
show high level of "scientific consensus" or, on the
contrary, different scientific paradigms, which are
conflicting. As Hjorland pointed out, to recognize
the existence of "scientific communities" seems very
similar to Thomas Kuhn's theory of "scientific paradigms"
(Kuhn 1962), that is, of scientific patterns
considered as dominant, successful and universally
accepted during an historical time. The substitution
of a scientific paradigm with another constitutes, in
Kuhn's view, a scientific revolution.