W Edwards Deming

Deming's View of Process

PMI was founded in the USA in the early 1980s by associates of Dr W. Edwards Deming. Our view of processes is informed by Deming's "System of Profound Knowledge" which underpins our application of specific methods from the Lean Six Sigma toolkit.

Processes are not like physical objects. Processes are characterised by changeability, variability, and uncertainty. Our common sense view of the world is optimised to deal with tangible objects, which do not tend to exhibit these characteristics. We unconsciously use conceptual short cuts that work for thinking about things but that don’t work so well for thinking about processes.

In his 1993 book "The New Economics", W. Edwards Deming proposed what he called a “System of Profound Knowledge” that captures four dimensions that offer important insights into process behaviour. Deming’s categorisation is very insightful, and can usefully be combined with additional research developments that have matured since the original scheme was proposed.


´┐╝Appreciation for a System - systems are built up of interlinked and interdependent processes, and care must be taken when looking at processes in isolation. Seeking to optimise the performance of a particular process within the  system will probably lead to sub optimisation of the system as a whole.

Understanding Variation - processes transform variable inputs into variable outputs. The process must be able to absorb the variability of its inputs in order to deliver outputs whose variability is within customer requirements. We have to understand the nature of the variation to determine appropriate courses of action.

Understanding of Psychology - processes take place in a human context. Individual and collective behaviours are a mix of the rational and the intuitive. Our common sense mental models of the world aren’t exactly reliable in predicting the behaviours of complex chains and loops of causality. We tend to over-estimate the degree of personal impact that individuals have, and to under-estimate the impact of chance variations. When a bunch of people are involved, the individuals’ differing tacit assumptions, values and cognitive preferences have a major impact on the performance of a process and especially on efforts to change and improve the process.

Theory of Knowledge - “facts” are mediated by theories. We are predisposed to see what we expect to see, and need to take active steps to check our theories and look for evidence to disprove them. As Mark Twain once put it “it ain’t what you know that’s the problem, it’s what you know that ain’t so”. Deming’s view of the theory of knowledge is compatible with that of the influential philosopher Karl Popper, who showed that whilst one can never prove anything to be true, one can reasonably strive to progressively improve the quality and accuracy of one’s models - theories - as to how the system behaves.

Deming's System of Profound Knowledge complements and enhances financial and discipline specific views of organisations.

PMI's training courses were originally developed by associates of W. Edwards Deming as a practical way to apply his teachings.