From Of Beards and Men, by Christopher Oldstone-Moore, which will be published next month by the University of Chicago Press. Oldstone-Moore is a senior lecturer in history at Wright State University, in Dayton, Ohio.

Philosophers and physicians of classical Greece, including Hippocrates, believed that hair in general, and the beard in particular, was a manifestation of male superiority. Men had greater “vital heat” than women or children, and this heat accounted for the greater hairiness of men, as well as their greater size, strength, and reasoning powers. The purified essence of this vital heat was semen. Introduced into a…