12/02/2025
I remember as a sergeant in the East Precinct we needed something out of a locked storage unit. It was a combination lock that was far from cheap. A sergeant on the watch before mine said his lieutenant had Argents put the lock on because she was tired of the other units taking their gear while they were off duty. Both of them were sure they were the smartest pair in the building. Despite their close working relationship, she hadn't shared the combination with the sergeant. We didn't have cellphones back then, so there was no way for him to call her at home. While the other sergeant paced the floor of the watch commander's office, I checked the time sheets for the missing lieutenant's serial number, knowing her vanity. I cracked the combination in a few seconds. It was based on her real serial number, either straight-forward or in reverse. The flummoxed sergeant is extremely left brained, while I have the power of right brained intuition.
At 15 years old, Richard Feynman taught himself calculus.
Not from a high school class—those didn't exist yet for advanced mathematics in 1930s America. Not from a tutor or private lessons. From a book called "Calculus for the Practical Man" that he bought himself and worked through in his bedroom.
By the time he finished, he'd mastered trigonometry, advanced algebra, infinite series, analytic geometry, and both differential and integral calculus. All on his own. All before entering college.
His father—who couldn't understand the book—was shocked when his teenage son explained concepts that baffled him. "It was the first time I realized that I could understand what he couldn't understand," Feynman later recalled.
That same curiosity-driven, self-teaching approach would define Feynman's entire career. He'd go on to win the Nobel Prize in Physics in 1965, pioneer quantum electrodynamics, invent Feynman diagrams that revolutionized how physicists visualize particle interactions, and become one of the most influential scientists of the 20th century.
But perhaps the most entertaining application of his "learning by doing" philosophy came during World War II, when he joined the Manhattan Project at Los Alamos—and became the lab's most notorious safecracker.
The Problem
Los Alamos in 1943 was the most secretive place in America. The world's greatest scientific minds had been assembled in the New Mexico desert to build the atomic bomb. Everything about the project—the physics, the engineering, the calculations—was classified.
You'd think security would be airtight.
It wasn't.
When Feynman arrived, he discovered that important atomic research documents were stored in filing cabinets locked with simple padlocks. "They were as easy as pie to open," he later wrote. You could pick them with a screwdriver and a bent paperclip.
Feynman pointed this out to military police and lab security. They ignored him.
So he decided to prove his point by actually opening the cabinets, taking documents he needed, and returning them with notes: "Thanks for your report."
The officials finally installed better locks—combination safes with supposedly one million possible combinations.
For Feynman, who loved puzzles the way other people loved sports, this was irresistible.
The Method
The standard safecracking book he bought suggested looking for numbers with personal meaning—birthdays, anniversaries, addresses. Feynman dismissed this as too time-consuming and turned instead to mathematics.
He discovered that the combination wheels didn't need to be exactly right—you could be off by two numbers in either direction and the mechanism would still work. This reduced the million possibilities to about 8,000.
He developed a technique for determining two of the three numbers if he could observe the safe while it was open. By leaning casually against someone's safe during a conversation and wiggling the dial, he could feel the mechanism and figure out the middle numbers.
He kept records. Whenever he was in someone's office, he'd surreptitiously lean on their safe and jot down two of their three numbers. Later, if he needed something from that office, he only had to try about 20 combinations to open it.
But the real breakthrough came from understanding his colleagues.
The Pattern
One day Feynman needed a document. The library was closed—it was a weekend—but he knew his colleague Frederic de Hoffmann kept copies of everything in his nine filing cabinets. All locked with combination safes. All combinations Feynman had never attempted.
He was stuck. The mathematical approach would take hours.
Then he remembered what the safecracking book had said: people use numbers with personal meaning. What numbers would a physicist find meaningful?
He wandered through de Hoffmann's office looking for clues. In the secretary's desk, he found a piece of paper with "pi = 3.14159" written on top.
Physicists love pi.
Feynman tried variations: 27-18-28 (e, the base of natural logarithms, written as 2.71828). Didn't work.
31-41-59 (the digits of pi: 3.14159). The safe clicked open.
From that moment, Feynman developed a reputation as a master safecracker. What people didn't know was that he had a secret weapon: physicists were extraordinarily predictable.
They'd use mathematical constants. They'd use the default manufacturer settings (one in five never bothered to change them). They'd use numbers like 10-20-30 or 20-40-60—nice, round, evenly spaced digits that appealed to their mathematical minds.
The world's most brilliant scientists, working on history's most important military secret, were securing their safes with the first digits of pi.
The Legend
Feynman's safecracking became part of Los Alamos folklore. Whenever someone needed a document from a locked cabinet and the owner was out of town, they'd call Feynman. He'd show up, work for a few minutes, and pop it open.
To demonstrate the absurdity of the security, he started leaving notes in safes: "I borrowed document no. LA 4312—Feynman."
One time he left a series of notes in de Hoffmann's cabinets signed "Same Guy" and "Wise Guy." When de Hoffmann discovered them, he panicked, convinced a Soviet spy had infiltrated Los Alamos and was methodically breaking into every cabinet. Feynman watched the panic attack unfold in real-time, then directed him to the final cabinet containing a note with Feynman's actual name.
De Hoffmann, relieved the secrets were still safe, hugged him instead of killing him.
The Philosophy
In his memoir "Surely You're Joking, Mr. Feynman!"—where he devoted an entire chapter to "Safecracker Meets Safecracker"—Feynman explained his motivation: "The key to my interest in all this is probably because I like puzzles so much. Each lock is just like a puzzle you have to open without forcing it."
It wasn't about theft. It was never about theft. Feynman could have stolen atomic secrets countless times. He had access to safes containing formulas for exactly how much uranium you needed for a bomb, theories for how it would work, calculations for neutron release rates—"the WHOLE DAMN THING," as he put it.
He never took anything except documents he needed for his own work, which he always returned.
The point was exposing how terrible the security was. The point was showing that brilliance in physics doesn't translate to wisdom in security. The point was that human nature—our tendency toward patterns, toward familiar numbers, toward not bothering to change default settings—creates vulnerabilities that no amount of mathematical complexity can overcome.
The same curiosity that led a 15-year-old to teach himself calculus led a 24-year-old physicist to become Los Alamos's premier safecracker—not to steal secrets, but to understand how things worked.
The Legacy
Feynman went on to transform physics. His work on quantum electrodynamics earned him the Nobel Prize. His Feynman diagrams are still used by physicists worldwide. His lectures at Caltech became legendary. He served on the commission investigating the Challenger space shuttle disaster and dramatically revealed the cause by dropping an O-ring in ice water during a televised hearing.
But ask anyone who's read "Surely You're Joking, Mr. Feynman!" and they'll remember the safecracking stories.
Because they perfectly capture who Feynman was: endlessly curious, fundamentally playful, learning by doing rather than by instruction, solving puzzles because puzzles are interesting.
The atomic bomb was built by the greatest concentration of scientific genius in history. Their research was protected by combination locks that they secured with the digits of pi.
Some of them even used the manufacturer's default settings.
The teenage kid who taught himself calculus from a book understood something important: being smart in one domain doesn't make you smart in every domain. Brilliant physicists could be terrible at security. Mathematical genius could coexist with predictable human behavior.
And sometimes the best way to prove a point isn't to write a memo—it's to actually crack the safes and leave notes proving you could do it.
Feynman died in 1988, but his philosophy endures: approach life with curiosity, learn by actually doing things, question authority, play with problems until you understand them, and never assume that conventional wisdom is correct just because smart people believe it.
Also: if you're a physicist, please don't use pi as your safe combination.
