Last year, I began reading books from the Personal MBA Recommended Reading List, a collection of 100 best books about business. One of the books I read was The Goal: A Process of Ongoing Improvement by Eliyahu Goldratt.
The Goal is a “business novel,” which means it presents didactic business-related ideas in a narrative form. I quickly read The Goal, its sequel, and most of the other business novels authored by Goldratt, his collaborators, and his imitators.
Goldratt’s books were inspiring, but left me with a lack of actionable information. I didn’t truly understand the ideas he was recommending, much less how to implement them in the workplace. As others have noted, sometimes the very people who create powerful new ideas are not the best people to explain and spread their ideas.
If I was just interested in business, this would have been a little annoying but not the end of the world. After all, I’m not especially interested in the places where his books are set, manufacturing and retail businesses. But I understood Goldratt to be saying that his ideas did not apply solely to business. As Goldratt’s life and career progressed, The Theory of Constraints became generalized into something called the “Logical Thinking Processes”- a series of thinking tools that would help diagnose and resolve problems in any system at all.
Of the Goldratt books I read, the Logical Thinking Processes are most elaborated on in It’s Not Luck, the sequel to the Goal. Much of the book details the protagonist’s business problems, but there is a significant side plot involving his family. The protagonist’s wife urges him to apply the tools he has learned along the way in his business life to his personal life, in particular the conflicts he experiences with his children. Goldratt detailed what the Thinking Processes were and made a convincing case that they were useful, but again, I didn’t know how to use them.
In researching the Theory of Constraints, I learned about a book on the Logical Thinking Processes by William Dettmer; Dettmer’s book, The Logical Thinking Process: A Systems Approach to Complex Problem Solving, is widely considered to be the de facto resource on learning + applying Goldratt’s ideas. Goldratt’s books are novels and a few dense nonfiction works, Dettmer’s book is a textbook, with a clear, logical, if dry account of Goldratt’s ideas.
At my college, it was common for groups of students and professors to meet for “study groups” — not groups to study core material in the classes, but to study supplementary material of shared interest. I participated in and created several study groups — e.g., one on Pierre Hadot’s Philosophy as a Way of Life, or another on a treatise by Josiah Royce. I found study groups to be an excellent way to learn new things and to learn from others, as well. So I thought, why not form a study group about Dettmer’s book?
I asked my friend Benjamin Mosior to do a study group on the book with me. Ben already had a copy of Dettmer’s book (it is a little expensive — my copy cost $45 with shipping), as well the interest to study Dettmer in depth.
In my college study groups, when I studied a book with others, we would read an assigned reading, and then discuss the reading, either clarifying what we didn’t understand, or considering its implications. My study group with Ben took a slightly different approach. We also picked readings to read together, but spent our scheduled meetings applying the ideas in the book, usually using Flying Logic, a tool for creating the diagrams that the Logical Thinking Processes are built on.
Having finished the book, I’m really grateful for the book. It provides much more clarity about how to implement an important swath of Goldratt’s ideas, specifically the Logical Thinking Processes, their diagrams + applications. Here is an excerpt from the end of the book, which summarizes the main ideas it addresses:
Everything that happens in this world is subject to cause and effect.
The rules of cause and effect (Categories of Legitimate Reservation) are universally applicable to any logic-based situation.
A Goal Tree can provide a benchmark for desirable performance.
A Current Reality Tree can reveal the interdependent cause-and-effect relationships behind deviations from desired performance.
Evaporating Clouds can help resolve apparently intractable dilemmas, which often perpetuate critical root causes of undesirable effects.
A Future Reality Tree can provide a robust “bench test” of proposed solutions, complete with consideration of potentially undesirable outcomes — unintended consequences — that might be associated with them.
Prerequisite Trees are the bridge between logically constructed solutions and their implementation.
Using the Thinking Process, you can start with an ill-defined problem and end with an implementation plan for a solution that offers a high probability of success.
Logical solutions are not enough. Implementation requires effective leadership and careful consideration of human psychology.
Dettmer’s book mentions but does not go into detail about the ideas that emerged directly from the Theory of Constraints, like The Five Focusing Steps or Drum-Buffer-Rope, or Critical Chain Project Management; it is also tantalizingly quiet about the ideas addressed briefly in the last chapter, namely the human element of creating change in organizations and other systems. However, it is quite clear about the core parts and steps of the Logical Thinking Processes. If I knew someone was interested in the Theory of Constraints, and actually applying the ideas, I would recommend Dettmer’s textbook as a must-read book.
Dettmer’s book is long, and somewhat dry. Because of the unusual quantity of diagrams in it, it also looks intimidating at first glance. I imagined that it would be a long, difficult read. I was surprised to find out that it was actually very approachable. Moreover, when you take care to actually apply the ideas to systems that are relevant to you, as Ben and I did, it also becomes surprisingly interesting. They are excellent tools for identifying + solving complex problems in a manageable way.
I have already tried making Goal Trees, Current Reality Trees, Evaporating Clouds, and Prerequisite Trees. I have not yet tried making a Future Reality Tree, and I could stand to use more practice applying the other trees, as well. I am sure I will do so, though. I am especially interested in applying these ideas to systems I participate in, whether they are for work or not.
If I experience particular problems, I will reach for the particular tools that are relevant to each kind of problem:
- If I need clarity about why I’m doing what I’m doing, I will try to create a Goal Tree.
- If there are a number of difficult problems, I will list them as Undesirable Effects and try to connect them with a Current Reality Tree so as to identify a small number of root causes, which I can try to solve directly.
- If I am experiencing a difficult conflict, I will reach for an Evaporating Cloud diagram to see if there’s a hidden assumption that might reveal an unexpected solution.
- If I have a solution that I want to implement, I will test it with a Future Reality Tree.
- If I am clear about what I want to achieve, but there are a number of complex, interrelated steps that I need to take to achieve that goal, I will reach for a Prerequisite Tree.
Goldratt’s books leave one with a sense of hope, that complex problems can be resolved, to great effect. Dettmer’s book leaves one with a clear direction towards the hard work required to actually do that. I’m grateful for the tools that Goldratt created and Dettmer expanded upon and presented, and look forward to continuing to applying the ideas in systems that I care about.