Abstract

In the late fifteenth century, clocks acquired minute hands. A century later, second hands appeared. But it wasn’t until the 1850s that a widespread need was felt for instruments that could recognize a tenth of a second. Once they did, the profound impact of these tiny moments was revealed as they related to broader conceptions about the nature of time, causality, and free will. Intimately connected to technologies that defined modernity (telegraphy, photography, cinematography), this talk locates the reverberations of this perceptual moment for science, philosophy and mass media. Once scientists associated the value with the speed of thought, they developed reaction time experiments with lasting implications for experimental psychology, physiology and optics. Astronomers and physicists struggled to control the profound consequences of results that were a tenth of a second off. And references to the interval were part of a general inquiry into time, consciousness, and sensory experience that involved rethinking the contributions of Descartes and Kant. This talk investigates how these moments defined modernity (and the place of fingers and eyes in it) by asking what it means to write the history of a radically different time period.