Nine Digits: A Brief History of Data, Privacy, and the SSN

Thursday, January 28 - 4 p.m. to 5 p.m.

Privacy Day discussion with guest speaker Sarah Igo

What’s in a number? In the case of the U.S. Social Security number, the now-familiar nine digits hold a fascinating story about modern citizenship, governance and data. Starting in 1936, the SSN was affixed to more and more American lives, spurring new uses of punch cards and filing systems as well as novel dilemmas about personal data. This talk gives a brief history of the SSN and what it reveals about the changing state of “our” information.

Denise Anthony, professor of health management and policy at the School of Public Health, facilitated Q&A time with Professor Igo after the presentation. They discussed shifting ideas of privacy, and how what we protect as private or share publicly has continually changed.


Event speaker Sarah Igo.

Sarah Igo

Vanderbilt University

Sarah E. Igo is the Andrew Jackson Professor of History and Director of the Program in American Studies, as well as the inaugural Faculty Director of E. Bronson Ingram College. She received her A.B. in Social Studies from Harvard University and her Ph.D. in History from Princeton University. Professor Igo’s primary research interests are in modern American cultural, intellectual, legal and political history, the history of the human sciences, the sociology of knowledge, and the history of the public sphere.

Igo’s most recent book, The Known Citizen: A History of Privacy in Modern America (Harvard University Press, 2018), traces U.S. debates that reshaped the meanings of privacy, beginning with “instantaneous photography” in the late nineteenth century and culminating in our present dilemmas over social media and big data.

Igo's first book, The Averaged American: Surveys, Citizens, and the Making of a Mass Public (Harvard University Press, 2007), explores the relationship between survey data—opinion polls, sex surveys, consumer research—and modern understandings of self and nation.

Full bio