So why will it not lie down and die? The reasons are to be found in the best features of the original
scheme and in the faith, determination and vision of many of its users. The reputation of BC was
firmly established on (i) a sound order of main classes (disciplines and sub-disciplines); (ii) careful
attention to the best collocation of related subjects at all levels; (iii) regard for what Bliss called the
scientific and educational consensus; (iv) liberal provision of alternatives; and (v) brief class marks.
Bliss was well aware that, in reducing to a single linear sequence the complex network of related areas
of knowledge which he had displayed schematically in two dimensions, much would be lost, but the
resulting main class order is certainly as good as that in any other scheme, and better than most. On
the face of it, this order may not be very significant, if the library is at all large, but in fact it can affect
the sequence of subordinate classes in turn, and at any point in a scheme, where the instruction occurs
to “divide like the whole classification”, absurdities in the main sequence can be seen in close
proximity. Whether there is, or ever was, a scientific and educational consensus regarding the ways in
which subjects are organized, researched and taught, or whether this was a notion advanced by Bliss to
justify the order he had arrived at, is fit matter for a medieval disputation. What is certain is that his
scheme appealed to librarians working in many different academic and special libraries, not least those
dealing with education. The fact that he provided so many alternative locations for subjects and so
many alternative arrangements within subjects – one of the most attractive and valuable features of the
scheme – shows that he recognized that his consensus was by no means of general or permanent
application. On notation, Bliss was as fanatical about achieving the shortest possible class marks
consistent with specificity as Ranganathan was about achieving totally hierarchical, expressive ones.