Varro, On the Latin Language, Book V, 61-2
“For this reason, everybody, when it is too hot or too moist, will either die or, if it persists, will be sterile. Summer and winter bear witness to this, since in the first, the air is hot and the wheat dries up, while in the other nature does not long to struggle with the rain and the cold to bring new life—instead, it waits for spring. Therefore, the roots of creation are two-fold: fire and water. For this reason there are placed at the threshold during wedding ceremonies since here is where things join and since the fire is male, which the semen is there, and the water is female, since a fetus develops from her moisture and the force of their binding together is Venus. This is why the comic poet says “Venus is his conqueress, do you see this?” not because Venus wants to conquer [vincere] but because she plans to bind [vincire].”
Inde omne corpus, ubi nimius ardor aut humor, aut interit aut, si manet, sterile. Cui testis aestas et hiems, quod in altera aer ardet et spica aret, in altera natura ad nascenda cum imbre et frigore luctare non volt et potius ver expectat. Igitur causa nascendi duplex: ignis et aqua. Ideo ea nuptiis in limine adhibentur, quod coniungitur hic, et mas ignis, quod ibi semen, aqua femina, quod fetus ab eius humore, et horum vinctionis vis Venus.
Huic victrix Venus, videsne haec?
Non quod vincere velit Venus, sed vincire.