In the Lean Six Sigma discussion group on LinkedIn, Brian P. Sheets argues that ” the alphabet soup of acronyms describing the multitude of process improvement & management methodologies that have come and gone over the last 50 years […]  is just plain, old, common sense.”  The list he targets in this statement is Six Sigma, TQM, BPR, BPM, TOC, MBO, Kaizen, and Gemba Kaizen, and overlap the one I discussed earlier in this blog. To support his argument, he invokes not only the great work done in US manufacturing during World War II without these acronyms, but goes back all the way to Egypt’s pyramids.

I see things differently. The old days were not so great and we have learned a few new tricks in the 68 years since the end of World War II, as a result of which we are not only able to make better products, but we also use fewer people to make them, at a higher quality. There definitely is something to some of the ideas that have been packaged under various brands in that time, and it is definitely more than common sense.

What is common sense anyway? The common sense approach to a problem is the solution that would be chosen by an intelligent person without any specialized knowledge. It is what you resort to when faced with a new situation you are unprepared for, like the businessman played by Anthony Hopkins in The Edge, who is stranded in the Alaskan wilderness by a plane crash and has to kill a grizzly.

Once you have been working on something for a few years, however, you are supposed to have acquired specialized knowledge of it, and apply solutions that are beyond common sense. And these solutions are counter-intuitive to anyone without this experience. Lean manufacturing concepts like one-piece flow or heijunka are bewildering to beginners, because they have nothing to go by beyond their common sense.

“Common sense,” Descartes said, “is the most fairly distributed thing in the world, for each one thinks he is so well-endowed with it that even those who are hardest to satisfy in all other matters are not in the habit of desiring more of it than they already have.” After that, he proceeds to explain a method “to seek truth in science” and presents three applications of this method, the best known being analytic geometry. All of this is far beyond common sense.

For all these reasons, I am not too fond of invoking common sense in support of any new concept. What you really need is a rationale, and experimental proof through a small scale implementation.