New technology solves centuries-old mystery

A mystery based on old technology — the question of who printed John Milton’s “Areopagitica” in 1644 — was solved by a team of Carnegie Mellon researchers using modern-day tools.

In 2019, the 375th anniversary of the printing of Milton’s treatise on freedom of the press, a team led by Christopher Warren, associate professor of English in CMU's Dietrich College of Humanities and Social Sciences, announced they had found that “Areopagitica” had been printed in London presses run by Matthew Simmons and Thomas Paine, and possibly Gregory Dexter.

The origin of the work, which established many of the principles of freedom of the press and freedom of expression used today, had been a mystery for centuries, because it was published anonymously, often a necessity for printers who wanted to avoid punishment or persecution.

"In Milton's time, printers could be jailed and even executed for printing controversial material. While Milton’s printers joined him in rejecting the notion that ideas had to be licensed before they could be printed, they also needed the protection of anonymity," Warren said. "The reason we haven't known who printed 'Areopagitica' is directly tied to the reason Milton had to write it. Those of us who benefit from press freedoms and freedom of speech sometimes forget the risks early printers took in producing controversial materials."

Warren and others on the team used computer vision and historical optical character recognition to help with the old-school method of identifying printers — matching the printed copies with known characteristics of each printer’s presses and typesets. Warren said the typesets were unique to each printer, and worn or damaged type, reflected in the printed works, helped to identify not only Simmons, Paine and Dexter, but several other controversial works of the time.

"This project shows just how much computer scientists, statisticians and humanists can learn by working together," said Shruti Rijhwani, a Ph.D. student in CMU's Language Technologies Institute, who developed the project's software along with Max G'Sell, assistant professor in the Department of Statistics & Data Science, and Taylor Berg-Kirkpatrick, a former faculty member in CMU’s School of Computer Science and current assistant professor in the Department of Computer Science and Engineering at the University of California, San Diego.