Over the years, significant...

[NNadir]

...[engineering design] theories and models under certainty have been quite successfully advanced through the use of classical mathematics. Probability and stochastic processes have further extended our abilities in analyzing [design] behavior under randomness (Haugen 1968, 1980, Siddall 1982, 1984, Keeney and Raiffa, 1976). Though our achievements have been gratifying in terms of formalism, we are still quite remote from an adequate description in terms of realism.

In our quest for objectivity, simplicity, and precision, we customarily fit [design] behavior to rigid mathematical models which make no provision for systems complexity and the imprecision in our cognition, perception, evaluation, and decisionmaking processes. Human subjectivity and imprecision have conventionally been regarded as absurd in scientific investigations. Being precise has been a virtue of science. Valuation is almost a forbidden word in formal models. Our unabating effort in achieving higher levels of precision has been the instrument of spectacular advancements in the physical sciences.''

Following the path of the physical sciences, [engineering design researchers] have come to believe that [design] systems are also precise in nature and can be efficiently analyzed by classical mathematics. To be precise, we have attempted to force artificial precision on imprecise phenomena and processes, and in so doing have lost the intrinsic imprecision in human systems in search of precision as a goal. In addition, we have failed to realize that our ability to be precise diminishes as the system becomes more complex. In cases of extreme complexity precision is usually an impossibility. [Design] models which neglect these intrinsic characteristics tend to be over-simplified, too mechanical, and too inflexible to give an adequate description of the complex and elastic real world.''

To have a closer approximation to and control of our [engineering design] systems, it is essential to restore human values and to treat imprecision with rigor in theory and model constructions...

Among existing methods fuzzy set theory appears to be a mathematical system which is instrumental in constructing formal models of imprecise [design] behavior. It allows us to restate the importance of treating human subjectivity, albeit imprecise, in model formulations. It can also provide a bridge between verbal and formal models...''

-Professor Yee Leung of the Department of Geography at the Chinese University of Hong Kong, in the preface of his book entitled: Spatial Analysis and Planning under Imprecision (North Holland, 1988, pages vii, viii).

A thought for the day...

I attended an interesting lecture by a sociology type today on the history of Soviet nuclear reactor design which made me think of this quote.