Collective Memory

We trace how societies remember and forget by mapping the stories, figures, and narratives that shape cultural identity over time.

Our research on collective memory explores how societies construct, preserve, and forget knowledge. We study memory as a large-scale process shaped by attention, language, and the technologies that record human activity.

Our work has documented the universal patterns governing the decay of collective memory, how linguistic connections shape the global reach of cultures, and how technological innovations such as printing, impact who becomes historically visible.

Building on these threads we have explored how historical knowledge flows shape the geography of cultural activities, have develop methods to estimate historical GDPs per capita, and explored how people navigate knowledge repositories such as Wikipedia.

Much of this research leverages Pantheon, our open observatory of collective memory. Pantheon serves as both a data resource and experimental playground to explore how societies remember, who they forget, and how these patterns evolve.

Together, these strands form a unified research agenda: to understand collective memory as a dynamic system shaped by attention, language, technology, and knowledge diffusion. For students and researchers, the Center for Collective Learning offers a unique environment to advance a quantitative science of memory that connects

The Global Language Network

People have long debated about the global influence of languages. The speculations that fuel this debate, however, rely on measures of language importance—such as income and population—that lack external validation as measures of a language’s global influence. Here we introduce a metric of a language’s global influence based on its position in the network connecting languages that are co-spoken. We show that the connectivity of a language in this network, after controlling for the number of speakers of a language and their income, remains a strong predictor of a language’s influence when validated against two independent measures of the cultural content produced by a language’s speakers. Continue reading at PNAS (link)

Pantheon

Pantheon (2013-today) is an effort to map our species collective memory by structuring data on the biographies of globally famous individuals.

Related Papers

8.-MILGRAM’S EXPERIMENT IN THE KNOWLEDGE SPACE: INDIVIDUAL NAVIGATION STRATEGIES
Manran Zhu, János Kertész
EPJ Data Science (2025)
Published Version (PDF)

7.-AUGMENTING THE AVAILABILITY OF HISTORICAL GDP PER CAPITA ESTIMATES THROUGH MACHINE LEARNING
Philipp Koch, Viktor Stojkoski, César A. Hidalgo
PNAS (2024)
Published Version (PDF)

6.-INDIVIDUAL DIFFERENCES IN KNOWLEDGE NETWORK NAVIGATION
Manran Zhu, Taha Yasseri, János Kertész
Scientific Reports (2024)
Published Veriosn (PDF)

5.-THE ROLE OF IMMIGRANTS, EMIGRANTS AND LOCALS IN THE HISTORICAL FORMATION OF EUROPEAN KNOWLEDGE AGGLOMERATIONS
Philipp Koch, Viktor Stojkoski, and César A. Hidalgo
Regional Studies (2023)
Published Version (PDF)

4.- HOW THE MEDIUM SHAPES THE MESSAGE: PRINTING AND THE RISE OF THE ARTS AND SCIENCES
Cristian Jara-Figueroa, Amy Yu, César A. Hidalgo.
PLoS ONE 14(2): e0205771 (2019)
Published Version (PDF)

PRESS: El Pais | Verne |

4.-THE UNIVERSAL DECAY OF COLLECTIVE MEMORY AND ATTENTION
CRISTIAN CANDIA-CASTRO-VALLEJOS, CRISTIAN JARA-FIGUEROA, CARLOS RODRIGUEZ-SICKERT, ALBERT-LASZLO BARABASI & CÉSAR A. HIDALGO,
Nature Human Behaviour 3:82–91 (2019)
Published Version (PDF)

3. PANTHEON 1.0, A MANUALLY VERIFIED DATASET OF GLOBALLY FAMOUS BIOGRAPHIES
AMY Z YU, SHAHAR RONEN, KEVIN HU, TIFFANY LU, AND CÉSAR A. HIDALGO
Scientific Data (3) (2016)
Published Version (PDF)

PRESS: NATURE PHYSICS

2. LINKS THAT SPEAK: THE GLOBAL LANGUAGE NETWORK AND ITS ASSOCIATION WITH GLOBAL FAME
SHAHAR RONEN, BRUNO GONÇALVES, KEVIN HU, ALESSANDRO VESPIGNANI, STEVEN PINKER, AND CÉSAR A. HIDALGO
Proceedings of the National Academy of Sciences 10.1073/pnas.1410931111 (2014)
Published Version (PDF)

1. THE EFFECT OF SOCIAL INTERACTIONS IN THE PRIMARY LIFE CYCLE OF MOTION PICTURES
CÉSAR A HIDALGO, ALEJANDRA CASTRO, CARLOS RODRIGUEZ-SICKERT
New Journal of Physics 8 52 (2006)
Published Version (PDF)