Chapter V

In order to understand of sterility in the male, we must take other symptoms. These will appear very easy, if he copulates with other women, and impregnates them. When the sexes do not appear to concur with each other, although all the before-mentioned circumstances are present, they do not have children together. For it is evident that this is the only reason of sterility: for if the woman contributes to the semen and generation, it is evident that both the sexes should be concurrent: for if the man is quick, and the woman slow, in the emission of the semen (and many women are comparatively slow), this will prevent conception; for which cause they do not produce children by sexual union with each other. They do so, however, when they happen to be concurrent with each other; for if the woman is desirous, and prepared for the intercourse, and is inclined for it, but the man is suffering previous pain, and of a cold disposition, it is then also necessary that they should be concurrent.