On Liberty: Evidence of Harriet Taylor Mill’s Co-Authorship

computer aided analysis. KIT researchers extracted the styles of some 270 books and articles by Harriet Taylor and John Stuart Mill. (Photo: Amadeus Bramsiepe, KIT)

On Liberty of 1859 is one of the most influential works in the history of philosophy. John Stuart Mill repeatedly stated that it was a joint venture with his wife. However, the philosophical canon still attributes it to him alone. A computer-aided study by researchers at the Karlsruhe Institute of Technology (KIT) now reveals that, with a high degree of certainty, On Liberty was not written solely by him. Long passages were texted by Harriet Taylor Mill or by both together. The researchers report in Utilitas. (DOI: 10.1017/S0953820821000339)

“Like everything I have written for many years, [On Liberty] it belongs as much to her as it does to me,” declared philosopher and economist John Stuart Mill in dedication to his wife, who had died a year before printing. However, he decided not to name Harriet Taylor Mill as co-author of the title. A research group in the Department of Philosophy at KIT’s Institute for Technological Futures (ITZ) has now used digital stylometry to determine the contribution of women’s rights activist Harriet Taylor Mill. Using statistical computational methods, the style of writing was extracted from large sets of text. And the researchers found that while the evidence is inconclusive, the result is substantial enough for her to count as a co-author. “With a high degree of certainty, we can say that there is a different style than John Stuart Mill,” says Professor Michael Schefczyk, ITZ.

Digital stylometry: artificial intelligence reveals characteristic text patterns

For reference, the researchers used artificial intelligence methods to analyze some 270 books and articles written by either John Stuart Mill or Harriet Taylor Mill or both together. Based on the frequency of certain words in the texts, machine learning algorithms extracted characteristic style patterns for each of the authors and both authors together. The algorithms focused on unconsciously chosen function words, such as “and”, “or”, and sequences of characters and punctuation marks. This “stylometry” revealed that chapter 3 of On Liberty was probably written by an author other than John Stuart Mill. The entire chapter appears to have been written by Harriet Taylor Mill. “This is also plausible when looking at the content. The chapter deals with individual personal development and the importance of developing one’s own potential; this topic is known to have been very important to Harriet Taylor Mill,” says Dr. Christoph Schmidt-Petri, philosopher and Mill researcher at KIT. “Our study is of more than just academic interest. It is more about the question of whether a woman is the co-author of one of the most influential books in the philosophical canon,” says Schefczyk. “On Liberty significantly influenced legal thought and political culture in liberal societies,” he says. For historical correctness, the group now suggests that modern editions include both names in the title to make it clear that the text was co-authored by a woman.

In KIT, Harriet Taylor Mill’s contribution to On Liberty underwent digital text analysis (here in red).

The most likely author is shown at the bottom of the six diagrams, the second most likely at the top.

Although the results differ depending on the models used, they agree that some passages of the third

particular chapter correspond to the writing style of Harriet Taylor Mill. (Graphics: ITZ, KIT)

Digital Humanities: Increasing Importance of Computer-Assisted Methods in the Humanities

“Computer-assisted digital humanities methods are tools for verifying many statements in ideas and language history in a scientifically well-grounded way,” says Schmidt-Petri. Its use is not trivial and requires specialized knowledge and technical knowledge. Lilly Osburg, who studies European Culture and the History of Ideas (EUKLID) at KIT, is a co-author of the recent article. She greatly contributed to the study thanks to her data science skills. “Digital humanities will gain importance for fundamental research in this area,” Schmidt-Petri hopes. This will lead to special requirements to be met by future researchers and their university education.

Original Post

Christoph Schmidt-Petri, Michael Schefczyk, and Lilly Osburg: Who Wrote On Liberty? Stylometric Evidence for the Contribution of Harriet Taylor Mill; Utilitas, 2021. DOI: 10.1017/S0953820821000339


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