On the Definitions of Sufficiency and Elegance in Systems Design.

Despite elegance being universally recognized as a goal for system design, there is little guidance in the related research and literature that is relevant to the design, development, or evaluation of elegant systems. This paper begins by reviewing the rather loose usage of elegance as a property of a system and shows that there are both abstract and practical views. Further, from analysis of the practical views of elegance in systems, it is clear that most current definitions of elegance are focused on the sufficiency of the system as a solution to the stated problem, rather than on elegance, perse. This paper disambiguates the usage of sufficiency and elegance, offers a formal definition of the two terms, and then provides several simple examples by way of illustration. Elegance and sufficiency must be considered as separate properties of a system, if only because the essential act of validation is an examination of the sufficiency of a solution, not its elegance. Any system attribute desired by the customer must be included as part of the solution's sufficiency and designed into the solution, not be a serendipitous unintended outcome of that design. Sufficiency is shown to be binary—a solution is either sufficient or it is not—and there may be more than one sufficient solution. Elegance is then defined to be the least complex sufficient solution. Furthermore, an elegant solution must be sufficient, but a sufficient system does not have to be (and is not always desirable to be) elegant. [ABSTRACT FROM AUTHOR]