Who Built the Toyota Production System? A Recovered Archive and a Debate Worth Reading
Almost 30 years ago I launched Superfactory.com, born out of my own lean journey and a desire to share what I was learning - and to play with this new technology called "the internet." (Holy crap I'm old...) Over 20 years it grew into a substantial resource hub, with a monthly e-newsletter that peaked at nearly 100,000 subscribers, before I moved on to co-found Gemba Academy in 2012.
A few weeks ago I found a full backup of the articles contributed by some of the best lean minds of that era. To preserve and share I've added them to a new Superfactory Archives page with full attribution to the original authors.
Most hold up well, and some are even more relevant now than when they were written. A few are genuinely primary source material that you won't find anywhere else.
That last category is where things get interesting.
A gentleman's brawl
Late 2005 into 2006, Art Smalley and Norman Bodek (RIP) used Superfactory as the arena for one of the more substantive debates the lean world has ever had: who actually built the Toyota Production System, and what role did Shigeo Shingo really play?
Both men had standing. Smalley was one of the first foreign nationals to work directly for Toyota in Japan, spending a decade there before moving to McKinsey as their lean manufacturing expert. Bodek founded Productivity Press, published over 100 Japanese management books in English, and was the person who introduced Shingo's work to the Western world. He had known both Ohno and Shingo personally.
It started, as these things often do, with a respectful provocation. In December 2005, Smalley published "TPS vs. Lean and the Law of Unintended Consequences," a sharp critique of how Western lean implementations had drifted from Toyota's actual priorities. The article opened with a visit to a Toyota engine plant in West Virginia that had no value stream maps, no dedicated change agents, no U-shaped cells, yet was the most efficient engine operation in the United States. His point: the tools had become the goal, decoupled from the principles behind them. It's a thesis that's only gotten more relevant since 2005.
The debate about Shingo ignited a few months later. In April 2006, Smalley published "Shigeo Shingo's Influence on TPS," an interview with Isao Kato, a 35-year Toyota veteran who had personally coordinated Shingo's visits to the company. Kato's account was precise and meticulous. Shingo first came to Toyota in 1956, after the foundational concepts of JIT and Jidoka were already in place. He taught an industrial engineering course (the "P-Course") to about 3,000 engineers over 20 years, averaging 3 to 4 visits per year. His SMED contributions were largely accomplished at other companies, not Toyota itself; Toyota had already reduced die change times significantly on its own before and after Shingo's involvement. Kato was appreciative but firm: "There is simply no person in Toyota Motor Corporation that thinks Mr. Shingo invented TPS."
Bodek read it and was, in his own words, "considerably, to put it mildly, annoyed." His response, "Dr. Shigeo Shingo: The Greatest Manufacturing Consultant," came in June 2006. He called Shingo "the greatest manufacturing consultant of the last 100 years" and questioned whether the Kato who gave that interview actually understood what Shingo had contributed (he suggested the interviewee "probably was Dr. Shingo's chauffeur"). He cited the former Toyota chairman who said at the dedication of Toyota's first plant in China that "if it wasn't for that man's father, Toyota would not be where it is today." And he invoked the chicken-and-egg answer he'd gotten from Iwata and Nakao, two men who had spent 15 years working with both Ohno and Shingo, when he asked them who invented JIT.
Smalley, via Kato, responded in July 2006 with "Dr. Shigeo Shingo's P-Course and Contribution to TPS." This one is extraordinary. Kato laid out the full curriculum of the P-Course in detail, showing that it contained no JIT, no Jidoka, no kanban, no standardized work. He described Shingo's shift in attitude after the 1973 oil shock, when Toyota was the only major company in Japan to turn a profit and Shingo suddenly became very interested in studying TPS. He addressed errors in Shingo's 1983 SMED book about Toyota. And he identified a key structural problem: most of Shingo's later English-language fame rested on books written after 1980, when he had finished studying TPS, not during the years when the system was actually being built.
Bodek responded one more time in August 2006 with "Who Can Shout Louder?," a somewhat more measured piece that cited Ohno's own words from a 1976 JMA journal article crediting Shingo's SMED concept, noted that Ohno and Shingo had appeared as co-equal keynote speakers at the same conference, and made the point that Shingo's process-versus-operation distinction (X-axis vs. Y-axis, in Bodek's framing) was the conceptual foundation for teaching flow thinking to those thousands of Toyota engineers. Even if Shingo didn't invent the system, teaching 3,000 engineers to see processes differently matters.
Both arguments are largely correct, and the disagreement is partly definitional. If "inventing TPS" means creating its foundational concepts (JIT, Jidoka, the pull system), that happened before Shingo arrived. If it means shaping the thinking of thousands of engineers who then went on to implement and refine the system for decades, Shingo's contribution is harder to dismiss. Kato acknowledged the training influence; Bodek acknowledged Ohno's primacy. They were arguing about the relative weight of two things that were both true.
What makes this exchange extraordinary is what it is: a real-time debate between people who were actually in the room, not a Wikipedia summary or a secondary source written 40 years later. Smalley worked inside Toyota. Bodek had personal relationships with both Ohno and Shingo and published their books. Kato coordinated Shingo's visits for 20 years. These are primary sources, written from memory and conviction, and the fact that they contradict each other in interesting ways is a feature, not a bug.
The rest of the archive is worth exploring too.