3.2 Systems thinking

General systems theory is a branch of science that has emerged in the 20th century as a counter-point to the successful, but sometimes limited, reductionist approach to science.  The “systems paradigm is concerned with wholes and their properties.”   It is based on the recognition that a system has properties that emerge from, but transcend, the sum of its individual parts.  Systems can be both hierarchical and interpenetrating. There is a hierarchy of systems from simple thermostats to the space  shuttle, and from cells, to organs, to organisms, to organizations.  A human being (a system) plays roles in many different social systems (families, corporations, organizations).  A hospital is a component of both the health care system and the economic sys-tem.

There is a general systems principle that when one system exists to serve another (System A serves System B) the serving system must be understood in terms of the served system (System A must be understood in terms of System B).  Information systems exist to serve human activity systems, and, therefore, “information systems design must stem from a model of the activity system served.” 

The systems approach has had notable success in the creation of large, complex engineering artifacts.  Lessons learned from this systems approach can be applied to business information sys-tems where the problems are mechanical in nature.   More problematic in many ways are the so-called “soft” systems. “‘Hard’ systems thinking is goal-directed, in the sense that [it] begins with the definition of the desirable goal to be achieved.”  The essence of hard systems is design engineering of a well-known solution to a well-understood problem, where the effort is to choose the best among several alternative approaches.  By contrast, soft systems are “management problems … in social systems where the goals are often obscure.”

Critical to soft systems thinking is to avoid the trap of treating human systems as equivalent to more deterministic mechanical systems.  There is temptation to reduce information system projects to hard system problems.  In some cases this may be appropriate, if the requirements are simple, clear and well articulated.  However, this is increasingly the exception, rather than the rule in enterprise class information systems.