Einstein’s theory of general relativity was the major source of his fame, and it’s certainly his most well-known accomplishment. The theory solidified a connection between space and time that influenced the modern interpretation of physics and provided the foundation for a century-plus of accomplishments in physics. But Einstein himself acknowledged that he came upon his theory not only due to years of studying the sciences, but also his multidisciplinary studies in other areas. Einstein praised the works of philosophers Ernst Mach and David Hume for teaching him the abstract philosophies of space and time which he built upon. Indeed, in a 1915 letter to physicist and philosopher Moritz Schlick, he discussed his studies of Mach and

“much more Hume, whose Treatise on the Understanding I studied with zeal and admiration shortly before finding the theory of relativity. It is very possible that without these philosophical studies I would not have come to the solution.”

Einstein could have been a victim of recency bias but almost 35 years later, writing his 1949 Autobiographical Notes, he again acknowledged the much of the same:

“The type of critical reasoning required for the discovery of [relativity] was decisively furthered, in my case, especially by the reading of David Hume’s and Ernst Mach’s philosophical writings.”

Einstein had been expounding the benefits of multidisciplinary thinking years before it would enter the zeitgeist and mainstream academia. He realized, of all people, that an education that spanned disciplines was essential because it broadened understanding and that, to interpret the world, he must, of course, first understand its nature. While specialization is crucial, over reliance on a single discipline can lead to blind spots and catastrophic failures and by studying multiple fields, individuals can develop better judgment, prevent cognitive biases, and make better decisions. The value of such an education was summarized nowhere better than by Berkshire Hathaway’s Charlie Munger, decades after Einstein’s initial publication of the theory of relativity.

Munger argued that there was no single discipline that held all the answers and that the best thinkers integrated mental models from multiple fields to make better decisions. His infamous concept of a “latticework” of mental models referred to an interconnected mental web to guide the analysis of problems and prevent cognitive biases, namely Incentive-Caused Bias and Man-With-A-Hammer effect.

Munger himself would say that most people think they fully recognize the importance of how incentives and disincentives influence human behavior, but in reality are blinded by irrationality in their subconscious:

“A man has an accultured nature, making him a pretty decent fellow, and yet, driven both consciously and subconsciously by incentives, he drifts into immoral behavior to get what he wants - a result he facilitates by rationalizing his bad behavior.”

The infamous example of Incentive-Caused Bias was given of FedEx’s skyrocketing efficiency of overnight package-loading when employees’ pay structure shifted from an hourly wage to a wage paid upon completion of the task. As a result, the packages were loaded ahead of schedule and employees were able to go home early. Individuals act, whether they realize it or not, in ways that align with their personal incentives rather than broader truths.

In the same way, the Man-With-A-Hammer Effect also caused inefficient outcomes. To a man with a hammer, everything does indeed look like a nail, and experts with their knowledge-hammer will over apply their discipline to problems they aren’t suited for. Exercising multidisciplinarity, unlike these individuals, leads to more robust decision making and avoiding the failures associated with intellectual tunnel vision.

As the years passed, some, but not all institutions realized the value of multidisciplinarity in their own education and integrated it into their curriculum. Munger gave the examples of law, which taught negotiation (business and psychology) and game theory (math and economics). Economics took examples from biology in the Tragedy of the Commons and behavioral economics, which took from psychology. The examples continue. Medicine now has biotechnology, bringing in knowledge from biology and engineering and epidemiology, which uses biology and statistics. The aforementioned example from Einstein above might be one of the less well known - a combination of physics and philosophy, though Einstein’s case study is prime example that even though philosophy (and Hume and Mach, specifically) did not create relativity, they precluded it. Einstein’s ability to question fundamental assumptions about space and time was shaped - as he said himself - by his studies in philosophy.

The benefits of multidisciplinarity only reaches so far before it becomes folly: applying models across disciplines is not always successful (usually due to incentives and hammers). A famous application between Finance and Physics is found in the Nobel Prize-winning Black-Scholes model. Used to price financial derivatives, it was originally derived from the physics heat equation (which, alongside it’s wisdom, was the reason also for its downfall). A model from physics and designed for natural systems, Black Sholes was applied to financial markets and assumed continuous markets and Gaussian distributions of returns, and ignored the role of psychological and economic irrationalities and the frequency of Black Swan events. As a result, financial institutions treated financial markets like physical systems, a textbook definition of Man-With-A-Hammer Effect, and these same institutions experienced Incentive-Caused Bias and ignored long-term financial risks due to their short term profits.

Similar stories happen in Economics and Medicine. Purdue Pharma’s promotion of OxyContin as a non-addictive painkiller may be a marquee pharmaceutical fraud of the modern era, contributing to the deaths of over 600,000 people. Purdue incentivized doctors to prescribe more opioids with financial rewards and kickbacks. The consequence overprescription, widespread addiction, and the opioid epidemic. At the same time, hospitals were the institutions that suffered from Man-With-A-Hammer effect as they treated patient care like a business, where the satisfaction scores became the hammer. The result was that hospitals and doctors ignored addiction risks because the financial incentives favored pain relief over long-term health.

The obvious question then arises on how to best alleviate the issue of adverse consequences in multidisciplinarity. These tendencies do not exempt smart people. They do not target dumb people. The Munger approach would be to teach a latticework of mental models and their successes, but I would posit that equal (if not more) focus should be placed to the historical failures and pitfalls of multidisciplinarity. This alone is not an original thought. Even Cicero wrote in De Oratore (in 55 BC!) that being

“ignorant of what occurred before you were born is to remain always a child. For what is the worth of human life, unless it is woven into the life of our ancestors by the records of history?”

What happened in a failure, why it went wrong, and what could be done differently will be the necessary education to think clearly when a situation does not align exactly with the mental model taught in the classroom (and they seldom do). Furthermore, teaching when not to apply a model at all, a direct cure to Man-With-A-Hammer tendencies, is equally important. Considering and learning to predict unintended consequences and second, third, and fourth order thinking would reduce careless errors and a reliance on overly simplistic ideas.

Einstein’s breakthroughs in physics and Munger’s principles in business and investing both point to the same truth: the ability to think across disciplines is what separates mere specialists from innovators. They both recognized that education must go beyond mere specialization. Einstein, in particular, warned against an overly narrow focus, emphasizing the need for a broader intellectual foundation. The true goal of education should be to produce independent and critical thinkers that can navigate complex challenges among various disciplines. But should an education fail to reach and exceed such goals? One last time to Einstein’s wisdom in his Education for Independent Thought; the second- and third-order implications of his comments are left to the reader in his first exercise in multidisciplinarity:

“It is not enough to teach a man a specialty. Through it he may become a kind of useful machine but not a harmoniously developed personality. It is essential that the student acquire an understanding of and a lively feeling for values. He must acquire a vivid sense of the beautiful and of the morally good. Otherwise he – with his specialized knowledge – more closely resembles a well-trained dog than a harmoniously developed person. He must learn to understand the motives of human beings, their illusions and their sufferings, in order to acquire a proper relationship to individual fellow men and to the community.”