In 1645, as he was looking back at his long and successful career as a samurai, where a single loss often meant death, Miyamoto Musashi concluded that although rigorous sword practice was essential, it wasn’t enough. At the end of the first chapter of A Book of Five Rings, he also admonishes aspiring warriors to “Cultivate a wide variety of interests in the arts” and “Be knowledgable in a wide variety of occupations.”
Similarly, Boyd, who was was a keen student of Musashi, described his method as looking across a wide variety of fields — “domains” he called them — searching for underlying principles, “invariants.” He would then experiment with syntheses involving these principles until he evolved a solution to the problem he was working on. Because they involved bits and pieces from a variety of domains, he called these syntheses “snowmobiles” (skis, handlebar from a bicycle, etc.)
One of his early snowmobiles appeared in New Conception for Air-to-Air Combat, his first product after retiring from the Air Force:
and the domains included air-to-air combat, wars and raids, mathematical logic, thermodynamics, and quantum mechanics.
He made his methodology explicit at the beginning of Strategic Game, where he laid out the source domains:
Drawing on the sources listed at the end of Patterns of Conflict, the accession list of his material at the Marine Corps Library, and my own recollection, I expanded Chart 12 to include all his briefings:
Now, writing on Quartz.com, author Michael Simmons concludes that a similar methodology underpins the success of serial entrepreneur Elon Musk:
At first, Musk’s reading spanned science fiction, philosophy, religion, programming, and biographies of scientists, engineers, and entrepreneurs. As he got older, his reading and career interests spread to physics, engineering, product design, business, technology, and energy. This thirst for knowledge allowed him to get exposed to a variety of subjects he had never necessarily learned about in school.
Musk’s snowmobiles include PayPal, Tesla (the car and the solar power company), the Hyperloop, and SpaceX. Note that although Boyd’s and Musk’s domain sets overlap (no surprise — both technologists), Musk’s included religion and science fiction, two areas that didn’t interest Boyd. In that sense, perhaps, Musk carried the process even further than did Boyd.
An important point is that both Boyd and Musk developed a level of expertise in these fields, enough to recognize the fundamentals, the invariants, among them. You can’t do this simply by reading about them. You actually have to roll up your sleeves and try them. Build a little Fingerspitzengefühl. Eventually, as Boyd observed later in Strategic Game, you build a little of this intuitive feeling for the domains and a whole lot for the process itself:
The trick to all this seems to be to develop in yourself an attitude where this cross-specialty mining and refining becomes fun. Otherwise you won’t stick with it long enough to do you any good. Anybody who saw Boyd at the Wednesday evening happy hours at Ft. Myer could appreciate that he had certainly accomplished this.