Publishing History: This paper was first published as Warwick Business School Research Paper No 62. University of Warwick, Coventry CV4 7AL, United Kingdom, May 31, 1992. It was reprinted, with the addition of a preface, in Systemist Vol. 15 (1), Feb 1993.
Note on Figures. Figures 1 and 4 have been abstracted from the the figures that appeared in the original publication. This is to avoid any possibility of international copyright infringement.
Abstract
A number of logical problems in conceptual modelling can be
solved by expressing the models in the form of universal
statements. This leads to distinguishing two type of conceptual
model, those used in main stream SSM and those used in Multiview, on the basis of whether the universals are definitions or inductive hypotheses. The models can be formulated in the predicate calculus and these formulations can be converted into the rules of Knowledge Based Systems.
Introduction
There is an ongoing debate about how Conceptual Models can be
used in the process of information systems analysis and design
(see Mingers 1992). Much of this debate can be characterized by
its extreme generality. It has not been accompanied by a detailed
analysis of Wilson's Information Requirements Analysis (1984, 1990) or Avison & Wood-Harper's Multiview (1990). Both methods use Conceptual Models in information system design, and the proponents of both claim that these methods are well tried in practice.
In a separate development Probert (1990) has challenged the
fundamental basis of Conceptual Modelling. Wilson (1990) and Checkland &
Scholes (1990) claim that their Conceptual Models show logical
dependencies. Probert argues that their models cannot be logical
in any sense of the word. This argument can is answered in the
first section of the paper which also reveals two important facts
about Conceptual Models. The first fact is that the Conceptual
Models produced by Wilson and Checkland in their Soft Systems
Methodology (SSM) are "logical" in a quite different way from the
way in which the Multiview models are "logical". The second fact
is that an analysis of SSM Conceptual Models reveals hidden
premises. The elements in the models can be understood as
corresponding to particular statements. The hidden premises
correspond to universal statements. In the predicate calculus
Conceptual Models can be expressed entirely in universal form.
The universal/particular distinction has implications for
information system design. The rules for Knowledge Based Systems
can derived directly from universals. The argument, therefore, turns full circle. Objections to the logic of Conceptual Models prompts a deeper analysis, the deeper analysis shows how the models can reveal a logical structure suitable for information system design.
In spite of this, there are ambiguities about the status of SSM
models. This is brought out in the second section of the paper
which considers the origins of universals. Three types of
universal are identified: inductive hypotheses, value statements
and definitions. It is argued that the SSM models are
definitional. This creates problems in determining that a given
model has any relation to the real world because this would seem
to involve an inductive hypothesis.
Multiview models, by contrast, are collections of inductive
hypotheses. The third section argues that Multiview is faced with
a problem that is the opposite of SSM: a hypothesis can only be
formulated in a language, a language requires definitions and the
Multiview model building does not generate definitions.
The paper concludes by suggesting that a new type of model could
be constructed. The new models would include definitions and
inductive hypotheses thereby combining the advantages of the SSM
method with those of Multiview. A further feature could be the
inclusion of value statements. This would make the models
logically comprehensive as well as adding a new dimension to the
model building process.