Social Systems Engineering

2Uncertainty in the Design and Maintenance of Social Systems

William M. Bulleit

2.1 Introduction

Engineering design must be performed under a wide range of uncertainties. The uncertainties arise from a number of sources, leading to aleatory uncertainties (those related to inherent randomness) and epistemic uncertainties (those arising from limited knowledge). Systems where prototypes can be built and tested during the design process (e.g., automobile engines) generally exhibit a lower level of uncertainty than systems where prototypes cannot be used (e.g., bridges) (Bulleit, 2013). Social systems are non‐prototypical, since we cannot build a prototype of the system and test it during the design process. Most engineers today typically deal with systems that are simple or complicated. A simple system is generally a single component in a larger system. A complicated system is a combination of simple systems that exhibit component interactions, but generally the interactions do not lead to non‐intuitive system behaviour. Simple and complicated systems can be either prototypical or non‐prototypical.

Social systems are complex, and more likely a subset of complex referred to as complex adaptive. Complex and complex adaptive systems have components that are highly interconnected, with strong interactions. In the case of complex adaptive systems, they also include agents, such as humans, who can adapt their behaviour to each other and to the environment in which they live. These ...