Review of The Laws of Subtraction by Matthew May


First of all I would like to thank Matthew May for the opportunity to contribute a page to his book, and for the review copy of the book. With greater skill in subtraction, my days will be less full and future reviews will no doubt be more timely.
In an interview Matthew May describes subtraction as:


“…the art of removing anything excessive, confusing, wasteful, unnatural, hazardous, hard to use, or ugly…and the discipline to refrain from adding it in the first place.”

Whenever a book’s theme or title is one that can be reflected back on the structure and content of the book, it is tempting to do so. Does the book need 220 pages? Does it need 70+ vignettes? Why 6 laws of subtraction rather than five, or three? This is not merely a pedantic exercise, it may be the central question that the book raises; how do we know when to subtract and when to stop (to turn subtraction upon itself and stop subtracting)?
Any theory should be tested in three ways:

1. Is its truth or efficacy demonstrable by evidence? On this count I give the book half marks. While an abundance of social proof is presented, it was hard to find evidence of the type that isolated subtracted as the key factor in success of any of the examples. We could easily choose a success factor, collect vignettes and just-so stories, and present a new theory. For example we could use “timing” and build a case around “being at the right place at the right time, something good happens”. But unless we took into account the other factors leading up to being in the right place, and the effort in following through after grasping the opportunity it would not be scientifically valid. Subtraction may indeed be the differentiating factor in all of the examples cited, but it is left up to the reader to experiment and verify of disprove this notion. This is not a criticism of The Laws of Subtraction, as the book does not claim to be a scientific paper. It is more of a wish, as I believe in and try to practice subtraction and would not like to see it becoming a popular system of belief, which due to a lack rigor and proof, is eventually subsumed by the next idea.

2. Is it falsifiable? While there are hundreds of examples and stories that satisfy and convince the reader that the principle of subtraction is a real thing, we are not asked to imagine a scenario under which would render “when we remove just the right things in just the right way, something good happens”. While the idea resonates and is true from experience, it is practically a tautology due to its wording. Can we imagine a circumstance under which we remove just the right things in just the right way but something good does not happen? If we can’t it is impossible to call this a scientific theory, which it deserves to be.

3. Is it internally consistent? In other words, can the ideas and claims within the theory be applied to itself, or does the theory claim to be above its own standards? Can we apply the laws of subtraction to the laws of subtraction? Can the theory be improved in the future by removing lower quality elements? All scientific theories, if not all knowledge, improves over time as false assumptions are exposed and removed through experiments and experience. Can we improve upon the six laws to make them more elegant? No doubt we can, and a good place to start may be to restate the “just right” theory of subtraction in a way to make it falsifiable. Refinement through personal practice is also another good way to test its internal consistency.

Both the narrative scope of Subtraction the book and the application of the theory are broad and varied, for which we need to thank the author Matthew May. He illustrates the importance of subtraction from visual art to product design to rock gardens to city planning to film to development of scientific knowledge. He makes the case through a variety of personal stories, one-page vignettes from contributors, and leading research in neuroscience and human behavior. The book is highly readable and makes the reader easily feels the truth and simplicity of the main idea of this book.

Matthew May explains subtraction in an interview:

The key is to remove the stupid stuff: anything obviously excessive, confusing, wasteful, unnatural, hazardous, hard to use, or ugly. If you don’t know what that is, ask people on the receiving end of what you provide or produces. They are generally more than happy to tell you.

The importance of asking “people on the receiving end” of your service, product, experience or design effort cannot be trivialized. The lack of people engagement whether customers, leaders or employees, is broadly responsible for many faltering transformation efforts. Matthew May demonstrates that he is well aware of this through his writing, speaking and consulting work, and could have drawn more attention to this point in the book. The entire premise of removing “just the right things in just the right way” to bring about good things assumes that we have a powerful grasp of “just the right”. While this is easy to spot, document and connect to subtraction in retrospect, it is fiendishly difficult to do when staring at the excess and complexity in front of us. The methods to arrive at “just the right” are, in decreasing order of efficacy, listening carefully to customers, determined trial-and-error and long-term statistical inevitability (luck). When lacking, subtraction may start with adding customer engagement.

Lean manufacturing evolved over decades, built on a foundation of scientific rigor in quality control brought to Japan by Dr. Deming, combined with the dogged pursuit of “just in time” by Taiichi Ohno and others at Toyota. Various industrial engineering, human resource development and intelligent automation breakthroughs enabled this. Often this was helped by subtraction applied to borrowed methods such as TWI, Taylorism and statistics. While there was much subtraction both at the front line level through continuous improvement (kaizen) activity and at the theoretical level (from push-based execution to pull-based), the resulting Toyota Production System is intricate, complex and elegant in comparison either to where they started in the 1950s or to where many firms are today.

The methods of lean management, six sigma, agile and so forth have been misunderstood to mean simply removal of waste, overburden and/or variation. In fact it is not so simple as this. At the surface level it is true that these methods seek to maximize human happiness by removing those things that erode it. However many times this means adding steps, processes, checks and systems rather than subtracting anything. The result may be the subtraction of inventories, delays, defects and correction loops, transportation etc. but the action to achieve these reductions may well be to add team leaders and supervisors to enhance support to the front lines, to add the capability to use the andon cord in order stop to call for help, the addition of in process self-inspection to every step rather than relying on line-end inspection, the addition of a vast number of visual controls across the chain of processes to make the current status of work visible, the addition of structured morning meetings and daily routines where before there was none, and the list goes on. While the result of all of this is simplicity and subtraction of many wastes, perhaps only half of the 6 laws of subtraction are truly applied (2. simple rules, 4. intelligent constraints, 5 break).

Surely this is not to say that lean management does not apply subtraction, or that subtraction does not apply to business process redesign, leaving as an option the need to review the theory and/or its wording.

Another question this raises is whether there is a level of maturity and complexity that is required for subtraction to apply. If a product, service, experience, community or system is simple to the point of being incomplete or inadequate, are the laws of subtraction the right choice? There is an assumption of Western hemisphere abundance, an excess of choice, within the context of applying subtraction. Can we apply subtraction effectively to relieving the suffering of drought-caused famine? Or do we need considerable addition (wells, basic supplies, shelter) before considering subtraction? Do we add something but invoke the double-negative and call it “subtraction of what is missing”? Is subtraction an approach we can apply to bringing about goodness at all levels of the Maslow hierarchy, or only at the highest levels?

The Laws of Subtraction draws on traditions and cultural practices from east Asia. One such axiom is:
To gain knowledge add things everyday. To gain wisdom, remove things everyday.
In this book there are some great ideas and encouraging stories around success through subtraction. Begin by reading the book to add to your knowledge. Then subtract daily to gain wisdom.

1 Comment

  1. Yogesh

    April 13, 2013 - 3:53 am

    Article is excellent and agree 110% that to gain knowledge add things everyday. To gain wisdom, remove things everyday.
    Addition adds to the clutter and removing declutters at physical and mental level.