As to the share which each of the parents has in begetting the child, we will give the opinions of the ancients about it. Though it is apparent that the man's seed is the chief efficient being of the action, motion, and generation: yet that the woman affords seed and effectually contributes in that point to the procreation of the child, is evinced by strong reasons. In the first place, seminary vessels had been given her in vain, and genital testicles inverted, if the woman wanted seminal excrescence, for nature does nothing in vain; and therefore we must grant, they were made for the use of seed and procreation, and placed in their proper parts; both the testicles and the receptacles of seed, whose nature is to operate and afford virtue to the seed. And to prove this, there needs no stronger argument, say they, than that if a woman do not use copulation to eject her seed, she often falls into strange diseases, as appears by young men and virgins. A second reason they urge is, that although the society of a lawful bed consists not altogether in these things, yet it is apparent the female sex are never better pleased, nor appear more blythe and jocund, than when they are satisfied this way; which is an inducement to believe they have more pleasure and titulation therein than men. For since nature causes much delight to accompany ejection, by the breaking forth of the swelling spirits and the swiftness of the nerves; in which case the operation on the woman's part is double, she having an enjoyment both by reception and ejection, by which she is more delighted in. Hence it is, they say, that the child more frequently resembles the mother than the father, because the mother contributes more towards it. And they think it may be further instanced, from the endeared affection they bear them; for that, besides their contributing seminal matters, they feed and nourish the child with the purest fountain of blood, until its birth. Which opinion Galen affirms, by allowing children to participate most of the mother; and ascribes the difference of sex to the different operations of the menstrual blood; but this reason of the likeness he refers to the power of the seed; for, as the plants receive more nourishment from fruitful ground, than from the industry of the husbandman, so the infant receives more abundance from the mother than the father. For the seed of both is cherished in the womb, and then grows to perfection, being nourished with blood. And for this reason it is, they say, that children, for the most part, love their mothers best, because they receive the most of their substance from their mother; for about nine months she nourishes her child in the womb with the purest blood; then her love towards it newly born, and its likeness, do clearly show that the woman affords seed, and contributes more towards making the child than the man.