Venae spermaticae post aures: The early modern angiology-neurology of virility

The famous discussion of Scythian cross-dressers in Hippocrates' Airs Waters Places (Aer.) 22 puzzled perhaps most medieval and Renaissance medical authorities. The text wrestled with a pre-Hippocratic, encephalocentric theory of spermatogenesis. Modern reception of the convoluted hypothesis put forward here gradually distilled three etiologies of failing virility: impotence, subfertility, and unmanliness. A gradual shift is discernable from increasingly Galenic neuro-andrological theories (sixteenth century) to neuropsychiatric (late-seventeenth through eighteenth century), phrenological and psychopathological (early- and late-nineteenth century), and finally early psycho-endocrinological (early-twentieth century) ideas about masculinity. Aer. 22 was a ubiquitously recurring reference across all of these episodes, indeed well beyond medicine, rendering it a highly sensitive index of change in neurodevelopmental and neuropsychiatric thinking. The pre-Enlightenment, neurology-centric onset of this extended modern history of sexual/gender medicine is briefly discussed, as well as its phrenological afterlife.