Until well into the 17th century, knowledge of human semen and its role in reproduction and procreation was based on medical theories dating from antiquity (Procreation, theory of). Basically two contradictory figures of thought were on hand. Both were based on humoralism, which pictured female bodies as being moister and colder, male bodies dryer and warmer. The “one seed theory,” whose foundation had been laid by Aristotle in the 4th century BCE in De generatione animalium (“On the Generatio…