1.9 Increasing complication, complexity and risk: summary
The three levels of change problem, simplicity, complication and complexity, can be associated with craft, engineering and systems engineering knowledge. The three categories of change problem represent different levels of uncertainty of what needs to be done and how to do it. The greater uncertainty brings increased risk. Although we tend to be risk averse we will take on greater risk if the returns are commensurate with doing so.
Human experience can be divided into three worlds. The physical world of direct experience obeys Newtonian laws of cause and effect. The ways in which this world operates is a ‘known problem’. Its operation may be complicated but good explanatory models exist to help predict outcomes. Complexity may be added to the complication of the physical world by the actions or interactions of sentient creatures, especially human beings. There do not, as yet, exist good models for the operation of the sub-physical world. This may be a result of it being inherently unknowable or due to ‘hidden variables’. Whatever the reason, the behaviour of the sub-physical world remains mysterious and complex. The operation of the supra-physical world of systems, and increasingly of interconnected systems of systems, is similarly mysterious and becoming more so as interconnectedness and, therefore, complexity grow.
Summarise the reasons why systems engineering is important.
There are three justifications for systems engineering. The first is to prevent failure. The second justification arose from the need to be able to manage the increasing complexity of systems. The third reason for adopting systems engineering is the fact that customers for systems and stakeholders in them are becoming more unforgiving.