Hegel’s Kilogram: an InterCcECT lecture

Hegel’s theory of measure, articulated in the Science of Logic, was developed shortly after the foundation of the metric system in the late 18th century. The establishment of physical standards for the meter and the kilogram, fabricated and archived at the International Bureau of Weights and Measures in Sèvres in 1799, illustrates Hegel’s understanding of measure as “the concrete truth of being” in a curiously salient way, demanding consideration of the relation between scientific accuracy, metaphysical speculation, and material particularity. The metric system instantiated universal standards of measure in singular physical objects, themselves created through meticulous measurement practices, thus dramatizing the problem of grounding in relation to both particular metrical units and the practice of science in general.

What is at stake, conceptually and empirically, when these inaugural units are themselves redefined? Since the 1960s, key standards of the International System of Units (SI) have been redefined on the basis of numerical constants, such as the speed of light (c) and the elementary charge (e), rather than physical objects. This paper considers ongoing efforts to redefine the kilogram unit on the basis of the Planck constant, focusing in particular on Watt Balance experiments carried out at the National Institute of Standards and Technology. These experiments offer a fascinating contemporary case study of the problem of measure. Considering both their empirical operations and their conceptual implications, I argue that the redefinition of metrical units is a key site for thinking not only the imbrication of epistemology and ontology, but also for understanding the history of modernity at the crux of science and philosophy.