When standard measurement meets messy genitalia: Lessons from 20th century phallometry and cervimetry Rebecca L. Jackson a, * , Merlin Wassermann b a Department of History and Philosophy of Science and Medicine, Indiana University Bloomington, 1020 East Kirkwood Avenue, Ballantine Hall 913, Bloomington, IN 47405, USA b Ludwig-Maximilians-Universit€ at Munich, Elektrastraße 13, 81925, Munich, Germany ARTICLE INFO Keywords: Messiness Epistemology of measurement Biomedical measurement History and philosophy of science History of measurement Validity ABSTRACT This paper examines two episodes in the history and philosophy of phallometry and cervimetry in the second half of the 20th century. Phallometry is the measurement of the human penis with special devices (phallometers) in a psychophysiological context, while cervimetry is the measurement of the cervix in laboring women (by hand or by cervimeter). Despite decades of efforts to standardize these measuring practices, we still have only non-standard ways of measuring the dynamics of the cervix during labor as well as penile tumescence during arousal. We adopt the lens of “messiness” as an analytic tool in order to trace historical actors' methodological assumptions, goals, and decisions that were involved in their measuring practices. It will be argued that, far from being an a priori attribute, the “messiness” of biomedical phenomena (and how to best respond to it) depends on the actors' methodological priorities. What is “messy” is actively shaped (and re-shaped) by researchers' instrumental as- sumptions and theoretical commitments, as demonstrated in their method of measuring. This paper also offers a preview of early findings from our current research on the history of cervical measurement (Jackson) and phallic measurement (Wassermann). Drawing on primary source material we have analyzed, the argument will be developed in two parts. First, in the context of phallometry research: Two different and eventually diametrically opposed methodological approaches developed when confronted with “messy” human bodies and minds, a divergence which still exists today. Second, in the case of cervimetry research: “messiness” emerged when re- searchers tried to standardize the measurement of the human cervix, to no avail. Ironically, today's “messy” practice of measuring the cervix by hand has been continually justified by knowledge gained in the continued pursuit (and failure) of standardized replacements of this method. 1. Introduction This is a story about phallometry, the measurement of human penises in psychophysiological research—and cervimetry, the measurement of the cervix in pregnant women. This is also a story about failed attempts at achieving standardization, and what those failures can reveal about the biomedical gaze of those studying human genitalia. In the middle of the 20th century, researchers and clinicians took up cervimetric and phal- lometric methods in order to make knowledge claims about subjects' and patients' minds and bodies. As might be expected, they faced serious methodological difficulties in their endeavors—as is the case still today. We outline some of these difficulties here, using the lens of “messiness” as a powerful tool for examining the histories of cervimetry and phallom- etry (and, more broadly, the history of biomedical measurement). At the same time, bringing the instruments, actors, practices, environments, and debates of genitalia measurement to bear on “messiness” itself can be illuminating for how to employ this tool analytically and productively. The measurement of genitalia, barring some exceptions, has been largely neglected in history and philosophy of biomedical sciences up to now. We contribute a preview of our ongoing original research on two historical episodes to the discussion. Examining mid-20th-century phallometry and cervimetry side-by-side provides a new context in which to ask: What is the relationship between messy human bodies and minds and attempts at standardization? Or, to be more specific, what historical and epistemological relationships emerge when standardized instruments and procedures encounter the inherent variation of indi- vidual humans' physiology and psyche? Against the backdrop of stan- dardized instruments and methods, we discover the unruly variation of * Corresponding author. E-mail addresses: jacksrel@iu.edu (R.L. Jackson), merlin.wassermann@sz.de (M. Wassermann). Contents lists available at ScienceDirect Studies in History and Philosophy of Science journal homepage: www.elsevier.com/locate/shpsa https://doi.org/10.1016/j.shpsa.2022.06.014 0039-3681/© 2022 Elsevier Ltd. All rights reserved. Studies in History and Philosophy of Science 95 (2022) 37–49