History defies easy quantitative analysis. Every rule has an exception, and human events seem to follow a logic all their own. But a new paper published in the journal Science aims to change that. In “A Network Framework of Cultural History”, an interdisciplinary team of researchers uses methods developed in computer science and physics to reveal patterns of cultural change in Europe and North America. They use a large data set of “notable persons” dating as far back at 0 C.E. These records track the birth and death places of artists, political leaders, inventors, and a range of others who have left their mark on history. Included are over a million people ranging from Biblical figure King David to Elvis. This data lets the authors quantify shifting patterns of human movement and changes in the cultural landscape.
The movement of notable persons from birth to death places forms a network of migration. Hubs in the network where many such people end up reveal the cultural centers of an age. When records begin, approximately 2000 years ago, Rome was the clear cultural center of Europe. Notable individuals were born across the empire, and overwhelmingly made their way to the capital. Evidently, all roads do lead to Rome. This cultural hegemony persisted for over a thousand years. Only in the 16th century did regional centers- Paris, London, Amsterdam, Venice, and so on- begin to overtake Rome. Present day Europe displays different patterns in different regions. France is still dominated by Paris, with no competitor even coming close. Germany, on the other hand, has a number of prominent cities with no clear cultural center. North America’s shorter recorded history begins with the founding of cities like New York City and Boston, joined later by west coast hubs such as Los Angeles. The data shows that New York City and Hollywood/Los Angeles are two of the greatest attractors of notable people over the whole of history. On the other side of the equation, Illinois produces a disproportionate share of notable residents, who presumably don’t stick around all that long.
Interestingly, the scope of migration hasn’t changed all that much over the last thousand years. The median distance between birth and death did not even double between the 14th and 21st centuries. The typical notable figure of the 1300s died 214 km from where they were born, while the corresponding resident of the present day travels 382 km. Only a small set of outliers emerge over this time period: those who move between the coasts of the US. It seems that most people still don’t stray all that far from home.
The data reveals the dominance that large cities have on the formation of culture. The rate at which cities attract notable individuals displays the mathematical signature of a “rich-get-richer” effect, where central cities in the cultural landscape draw disproportionate numbers of important migrants who further enhance the importance of their new home. By contrast, it is much harder for a previously unknown city to rise to prominence. The authors place this finding in the broader context of studies showing that large cities boost productivity by drawing people together and letting them make the chance contacts that spark a new idea or help a venture get off the ground. If you want to change the world, or even just get your career off the ground, heading to the big city is likely the right move.
This work can serve as a blueprint for bringing quantitative methods to historical analysis. Mathematical and computational tools allow us to extract patterns and relationships, which can then be given narrative explanations. In the process, we learn a little more about the forces that drive human life.
Schich, Maximilian, Chaoming Song, Yong-Yeol Ahn, Alexander Mirsky, Mauro Martino, Albert-László Barabási, and Dirk Helbing. “A Network Framework of Cultural History.” Science 345.6169 (2014): 558-62. A Network Framework of Cultural History. 1 Aug. 2014. Web. <http://www.sciencemag.org/content/345/6196/558>.
Image courtesy of Wikimedia Commons.