Hans van den Berg

When Albert Einstein moved to Princeton, his wild hair and simple clothes often made him look like an absent-minded worker rather than a world-famous scientist. One day, he was even mistaken for an electrician. Someone asked him to fix a faulty light bulb socket. With a playful smile, Einstein quietly repaired it and said nothing about who he really was. Only after the job was done did he reveal his identity—leaving the staff red-faced and speechless. But this was not the first time he enjoyed a good role reversal. In the early days, when his theory of relativity had just begun to make headlines—especially after the 1919 solar eclipse proved him right—Einstein was invited to speak across the world. Yet few people knew what he looked like. On one trip in the United States, he admitted to his driver that he was tired of repeating the same lecture again and again. The driver, who looked a bit like him, joked, “I’ve heard your talk so many times, I could give it myself.” Einstein laughed—and then agreed. At the next conference, the driver went on stage as “Professor Einstein,” while the real Einstein sat quietly in the back. The driver delivered the lecture perfectly. No one suspected a thing. Then a proud professor in the audience stood up and asked a very difficult question. Einstein prepared to step in and confess the trick. But before he could rise, the driver calmly replied, “Sir, your question is so simple that even my driver, sitting at the back, can answer it.” All eyes turned. Einstein stood up, gave the correct answer, and saved the day. Later, the two men shared a hearty laugh. Whether this story is true or just a charming legend—sometimes told about another great scientist, Max Planck—it carries a clever lesson. Anyone can memorize a speech and repeat it smoothly. With practice, almost anyone can give a lecture that sounds impressive. But that does not mean they truly understand the subject. Psychologists call this “chauffeur knowledge.” It is the kind of knowledge that knows the words, but not the meaning. It shines on the outside—but inside, it may be empty. Einstein, of course, had the real thing.