Rebecca L. Jackson

This paper presents the peculiar story of the drop, a non-standard unit which outlived the standardizing forces of the late eighteenth and nineteenth centuries, as an instructive lens for understanding how and why non-standard units survive. With the establishment of the metric system in France came a large-scale discussion on the merits of various units, the drop among them. Some partisans of the metric system argued that this unstandardizable unit should be abandoned in favour of decimal weight units. Despite this, the drop remained in use in both lay and scientific contexts. By closely studying medical and chemical practice, we show that the drop was a rich tool for both communication and scientific quantification. The drop’s utility went beyond cases where achieving precision was superfluous; drops were also used by practitioners in ways that could not easily be replaced by the scales, accomplishing aims for which standard units were ill-adapted or even damaging to the task at hand. The drop’s familiar and flexible nature made it uniquely useful in instructions to be carried out by lay people or factory workers, as well as in the many experimental procedures that required the practitioner’s attention to be directed at sensory indications.

Outlining the Apgar Score’s use throughout the latter half of the twentieth century, I propose that the historical abuse of this score for newborn wellness does not only come from the obviously white-centered assessment criteria for “color” established in the 1950s. The more concerning aspect of the Score is its potential interpretation as measuring one unitary construct which captures both the past asphyxiated condition and future health risks of individual infants (a problem that has been noted for decades in professional guidance documents). My novel contribution is to use the history of the Apgar Score’s use and misuse to demonstrate why racial inequities in medicine pose a problem for two frameworks in philosophy of measurement when applied to patient outcome measures. I ultimately argue that the case of the Apgar Score shows how both dominant frameworks in philosophy of measurement, that of coordination (within the representational theory of measurement) and that of psychometric validity, fail to help us fully comprehend the challenge of clinical measuring with indices. Both frameworks expect that, at some point, the process of coordination or validation of an instrument will end. An expanded and historically-informed framework is warranted for understanding how patient outcome measures are validated (and re-validated) over time, which can include the social and institutional forces which render an index relevant, biased, or questionable for different aims.

This paper describes our reconstruction of the apparatus used in C.S. Peirce and Joseph Jastrow’s 1885 psychophysical experiment, “On Small Differences of Sensation” and how it relates to persistent questions in scientific theories of measurement. We situate Peirce and Jastrow’s work in the broader context of nineteenth-century discussions about the status of psychology as a science and emphasize the role of measurement and experiment in determining that status. Through our re-enactment of the experiment, we analyze the experiment’s methodology, which features blinding, randomization, noise control, and a technology for data recording. Our claims are illustrated by images of historical and reconstructed apparatuses, as well as graphs of the data collected in our reproduction. Our findings exemplify the relevance of history of psychology for contemporary philosophy of science and theories of measurement, and defend experimental reconstructions as a particularly fertile method of inquiry in the history of psychophysical sciences.

This dissertation examines three successful, patient-centric measuring practices in the Anglo-American clinical context, spanning from the early 19th century to today: (1) the use of “drops” as a fluid unit in medicine and pharmacy, (2) the measurement of cervical dilation by hand (digital cervimetry) for labor assessment, and (3) the Apgar Score for newborn health assessment. I also briefly introduce a discussion of (4) the Patient Generated Index (PGI) and the Schedule for Evaluation of Individualized Quality of Life (SEIQoL) for measuring patient status and outcomes. All four practices were developed to ensure preferable patient outcomes, at the expense of precisely representing empirical states. A better understanding of the “non-standard” clinical measuring practices of the 19th and 20th centuries shows that the ethical-epistemic challenge of having both “patient-centric” and “evidence-based” measurement has a much longer history than the recent emergence of these terms would suggest. I discuss the ethical and epistemic challenges which had to be overcome when validating these measures, and consider how the successful (and failed) endeavors of past practitioners can inform methodological issues faced in the formation of clinical indexes today. I introduce the notion of “epistemic audiences,” and argue that units (and accompanying scales) of measurement serve as “epistemic conduits” for these audiences, transforming observations into difference-making data toward relevant judgments and/or actions. By examining the ways that these non-standard measuring practices challenge dominant theoretical frameworks in philosophy of measurement, I form recommendations for how we can improve philosophy of measurement to better account for the historical success of these practices: (1) the scope of philosophy of measurement should expand to encompass entire measuring practices; (2) measurement success should be understood “ecologically,” as being fit within a “niche” of pragmatic, physical, and temporal constraints and demands; and (3) the “problem of coordination” should be extended to include the relevant set of judgments (the landscape of decision-making at hand), in order to move towards a clinically relevant philosophy of measurement.

. This paper follows the journey of two small fluid units throughout the nineteenth century in Anglo-American medicine and pharmacy, explaining how the non-uniform “drop” survived while the standardized minim became obsolete. I emphasize two roles these units needed to fulfill: that of a physical measuring device, and that of a rhetorical communication device. First, I discuss the challenges unique to measuring small amounts of fluid, outlining how the modern medicine dropper developed out of an effort to resolve problems with the “minimometer,” which measured minims. Second, I explain how drops, utilized in “the open drop method” of administering general anesthesia, effectively communicated a gradual process and epistemically valuable heuristic to the audience of practitioners, whose attention to individual medical outcomes was important for verifying the proper dosage. The standardized minim was never able to achieve success as the drop’s intended replacement; the non-uniform drop better served the relevant epistemic goals within the practical contexts for which these units were designed. The surprising historical trajectory of drops should cause us to question the common equivocation of “standardization” with “progress” in the history and philosophy of measurement. This study also exemplifies how examining non-standard measurement practices can be instructive for better understanding the role and function of standardization within epistemology of measurement.