From Physics to Product: The Importance of First Principles
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Back in my freshman year of college, while laboring under the misconception that I was an adept computer programmer and polymath of all things quantitative, I enrolled in a physics course. While I can hardly remember specific details of the class itself at this point, my recollection is that we sequentially learned the fundamental building blocks of physics: gravitational force, electromagnetic fields, momentum, and so on. The final exam of that class is what will be burned into my brain forever. While I had been able to muddle my way through the coursework’s individual sections well enough, the nature of the final exam posed an entirely different problem: to borrow from a recent, and excellent, movie, it was everything everywhere all at once. Questions like “calculate the strength of the magnetic field of an electromagnet rotating counter-clockwise as it accelerates at half the speed of light past a black hole.” (For any physics nerds wishing to tell me that this question makes no sense — that’s fine, it made no sense to me at the time either.) Years after this final exam used me to mop the floor, I realized where I had gone wrong. I was able to grasp physics at the surface level, which was sufficient to regurgitate the basic concepts and complete the course’s homework. However, the final exam had been testing for a first-principles understanding, not just of how objects and forces interacted, but why they interacted that way. To have a surface level understanding is to learn only the outcome (“gravity makes things fall down”) of a complex, and possibly probabilistic, system (“every particle in the universe attracts every other particle with a force that is proportional to the product of their masses and inversely proportional to the square of the distance between their centers”). When one or more aspects of the system are changed in unexpected ways, those who have a first principles understanding of the system should be able to reason their way to the new set of outcomes, whereas those with a surface level understanding will simply find themselves to be, as I was on the final exam, inexplicably wrong.
It’s debatable as to whether there are immutable laws in product management, or in business for that matter, but understanding the role from first principles is nonetheless imperative. The context in which a certain strategy or tactic is successful is inexorably changing, sometimes very slowly and sometimes extremely quickly (see: AI). Even within a given timeperiod, the context can vary dramatically from company to company. In my personal experience, working at Amazon and Walmart Labs back-to-back — two companies ostensibly in the same range of industries, selling much the same products to much the same customers — could not have been more different (in a nutshell: for any given problem, Amazon sought to find an automated solution, whereas Walmart threw an army of analysts at it.) Imagine my surprise one day walking down the hall of one of the Walmart offices and looking up to see Amazon’s leadership principles, verbatim but without attribution, stenciled in giant letters on the wall. Some executive had come to Walmart from Amazon and was attempting to bring with them the exact set of principles which had driven their prior success. This was a fascinating approach: rather than demonstrating a surface level understanding of why Amazon is successful and saying “we wrote PRDs at Amazon so now we will write PRDs at Walmart”, this executive was attempting to establish a culture of first principles. The Walmart team would be customer centric, they would insist on high standards, and they would invent and simplify — but the resulting artifacts, tactics and strategies would look quite different than they did at Amazon.
If you are storing away the product management lessons and strategies you learn with a binary “works / does not work” structure, you are setting yourself, the people you lead and the company you work for up for an inevitable failure at some point in the future when conditions change. How many of us have joined a new company and proposed a promising solution to a problem only to have it rejected with “we tried that n years ago and it didn’t work”? Or conversely, had a new executive join your company and repeat “here’s how we did things at my last company” ad nauseum? (I may or may not have been guilty of the latter in the past.) These are telltale signs of a surface level understanding. As Product Managers, and particularly as executives, we must be able to evaluate and convey the validity of ideas from first principles if we hope to maintain success across companies and over time.
