In 1828, Carl Fredrich Gauss, the “Prince of Mathematics,” traveled from his home in Göttingen, Germany, to Berlin at the invitation of Alexander von Humboldt, the world-renowned explorer. By the time of the meeting Gauss was already widely recognized as the greatest mathematician of his time. Some would even today a rank him as the greatest of all time. There is hardly a branch of modern mathematics that does not bear the imprint of his work. So well-known was he in his lifetime that it was said that Napoleon ordered his invading army to spare the city of Göttingen from destruction in recognition of Gauss’s residence there. Even readers with a general familiarity with these two historical figures might be puzzled why Humboldt the explorer was so interested in the work of a pure mathematician.
The answer is captured in an anecdote from Gauss’s early adult years incorporated into Daniel Kehlmann’s Measuring the World. For a time Gauss worked as a surveyor. Seeing Gauss at work in the field, his future wife asked him to explain what he was doing. He provided her and her friend an explanation suitable for a teenager with no knowledge of trigonometry. Joanna was puzzled. It didn’t make sense, she said. His measurements treated the earth as flat, but everyone knows it’s round. Gauss answered that in the limit it didn’t matter, which is an abstract way of saying that plane geometry and trigonometry work if they’re used for sufficiently small areas. Humboldt measured distances everywhere he explored, but the distances were great and measured by shooting the stars. To make accurate maps requires the geometry of the surface of a sphere, not a plane. This was one of many mathematical problems on which Gauss worked during his long career.
In Measuring the World, Daniel Kehlmann imagines what happened, and more important what Gauss and Humboldt were thinking, during this historic meeting. His novel goes on to provide this kind of biography of both Gauss and Humboldt, leading up to and then following the several days that they spent in each other’s company. The book is an example of fictionalized biography. Extrapolating from letters and contemporary reports, a novelist can help us project ourselves into the minds of real people who have played an important role in history.
One great advantage of this kind of fiction is that the writer doesn’t have to invent any scientific research. On the other hand, dialogue frequently has to be invented for real people, and it’s impossible to know for sure what is going through real people’s minds. Readers are at the mercy of the author’s ability to imagine these details. Both Gauss and Humboldt were notoriously quirky individuals, who rarely recorded their feelings. In fact, Humboldt’s diaries frustrate biographers because they are almost exclusively his objective observations — and measurements, accompanied with relevant calculations.
I purchased a copy of Vermessung der Welt in 2007 on a trip to Germany, where my wife and I attended language school and tried to learn German. At the time, I was just barely able to read fiction. But I didn’t realize that Kehlmman doesn’t use any direct quotations. Carol Brown Janeway preserves this stylistic feature in her 2006 translation. Here’s an example from p. 6 during Gauss’s journey to Berlin:
No passport, asked the gendarme, astonished, no piece of paper, no official stamp, nothing?
He had never needed such a thing, said Gauss. The last time he crossed the border from Hannover had been twenty years ago. There hadn’t been any problems then.
Eugen [Gauss’s son] tried to explain who they were, where they were going, and at whose bidding…
The German grammar requires different forms of verbs and pronouns for indirect quotations. When I realized at the beginning of the second chapter that the whole book was written this way, I gave up and bought the English translation! The book wasn’t going to teach me any conversational German! On the other hand, this linguistic trick helps to make the book work as a fictionalized biography. While I enjoyed much of the book, it was mostly due to the subject matter, two fascinating and peculiar individuals. Much as I enjoyed the book, it’s easy to appreciate why others may prefer to read two good biographies.