160. 4. A desire to unite her husband to her is constant and continual in a wife, but inconstant and intermittent in a husband. The reason is that love cannot help but love and unite itself in order to be loved in return, this being the very essence and life of love. And women are born forms of love, while men - with whom they unite themselves in order to be loved in return - are receivers. Moreover, love is continually operative. It is like heat, flames and fire, which die if they are prevented from operating. That is why a desire to unite her husband to her is constant and continual in a wife.
On the other hand, a husband does not have the same desire with respect to his wife, and that is because a man is not a form of love but only a form receptive of love. And a state of reception comes and goes, depending on other concerns which interrupt, depending on changing feelings of warmth or lack of warmth in the mind for various reasons, and depending on increases and decreases of the powers in the body. Because these things do not return in a constant fashion or at set times, it follows that a desire for this union is, in husbands, inconstant and intermittent.