Abstract Summary
In the nineteenth and twentieth centuries metaphors acquired biologies, and then biographies. Emerson, in 1842, said “Language is fossil poetry”; modernist poets and critics gave criteria for what made a “healthy metaphor”; and it became possible for a metaphor to die. A dead metaphor is a once-figurative expression whose figure, vivid in the past, is no longer apparent. In contrast, the figure in a live metaphor is present and active, wrenching around the order of things. Some causes of death are ascertainable by literary scholars; others need to concern historians of science. This paper shows how historians of science are in a privileged position to observe the lives and deaths of metaphors. My main exhibit will be metaphors of perception in late-nineteenth-century psychology and physiology. These are metaphors whose differences once formed the basis of theoretical disagreements, about the contribution of the perceiver and the integrity of the perceived. Since that period of diversity and contest, these metaphors—such as the “stream of consciousness”—have incurred death by two counts: death by consolidation and death by banality. I show how science is implicated in these deaths, by the changing of scientific theories and, equally, by theories consolidating or gaining empirical verification and acceptance—thus no longer requiring the epistemic work of a live metaphor. I argue that metaphors live precariously in science, but to mark their time of life is to restore their distinctive potency and to better recognize, for a particular historical moment, the nature of its epistemic freedom.