Pinpointing the Difference
Her Perfection
In the marital act which is ordered to generation, the male’s is the active role and the woman’s is passive. This is the case not only in the external act, but also in the internal act where the male sperm fertilizes the female ovum. Even in the development of the animal the crucial factor for determination of sex is the male chromosome and its genes.[1] Specific genes on the Y chromosome cause the flood of testosterone which specifies the developing individual as male, and these genes also provide instructions for making proteins involved in the processes of determining male sexual characteristics before birth. Not only will a female result without a Y chromosome, but if there is a defect in these genes on the Y chromosome, a male also will fail to develop, resulting in the development of a female. One might say that being female is the "default" of the matter,[2] and that the Y chromosome with its male-determining genes acts as an agent to determine the sex to male instead.
St. Thomas says that an active force, in this case the male, tends to the reproduction of its exact likeness, in this case the masculine sex, because nature intends the perfect effect of its own kind.[3] “Hence even a natural agent, being superior, makes the thing it acts on similar to itself.”[4] So it is only by an absence (of the Y chromosome) or a defect (of specific male genes) that a female is conceived. To say that “the female is a misbegotten male,”[5] as the ancient philosopher Aristotle proposed, is shown to be true in this limited sense, that the female results when the male ‘fails’ to develop.
Some have thought this idea of Aristotle to be anti-woman because they did not understand it in its philosophical context. However, St. Thomas goes on to say that the generation of a female is not a mistake.
As regards human nature in general, woman is not misbegotten, but is included in nature’s intention as directed to the work of generation. Now the general intention of nature depends on God, Who is the universal Author of nature. Therefore, in producing nature, God formed not only the male but also the female.[6]
With regard to universal nature, the female sex is its own perfection intended by nature, in the cosmic order designed by God.[7] A ‘failure’ of the male to develop in a particular instance, then, must not be considered a mistake or defect. The production of the female is both intentional and a perfection. Both females and males are necessary for the perfection of the universe.
Receptivity
In the reproductive act, man is the agent and woman is the patient, but the passivity proper to a female, again, is not a defect. Rather it is superior to other kinds of passivity. There are three different ways of being passive as described by St. Thomas. The first two involve something being taken away from a thing. One causes a defect, for example when a person suffers blindness. The other refers to being the direct object of any transitive action, whether what one suffers is good or bad. The third, however, is a passion that does not involve suffering a loss, but rather is a perfection.
Third, in a wide sense a thing is said to be passive, from the very fact that what is in potentiality to something receives that to which it was in potentiality, without being deprived of anything. And accordingly, whatever passes from potentiality to act, may be said to be passive, even when it is perfected. And thus with us to understand is to be passive. …This is made clear from the fact, that at first we are only in potentiality to understand, and afterwards we are made to understand actually. [8]
Given as an example of the third kind of passion that is receptive, is in the intellect, the highest faculty in a human. The intellect is in potency to know all things, but this very potency implies that it must receive what it does not have. The intellect’s thinking activity can only take place because of this receptivity. Further, it is because of the intellect’s receptivity that a human intellect can be united to God as an intelligible object in heaven, and so know Him. This act of knowing constitutes the intellect’s perfection, and yet its object must be received.
It is this third form of passivity, or better called ‘receptivity,’ that is in the nature of femininity. The intellect’s reception of a form is compared to a stamp in wax. Wax is able to ‘grab’ a form, due to the strength of its receptive nature, unlike water which though passive to the action of the stamp, is not so in a receptive way. In yet another way, a rock is strong but unyielding, and so again lacks the kind of passivity that is receptive of the stamp’s form. A woman’s receptivity, like the intellect's, can be compared to that of wax. She cannot be fruitful and gestate a child unless she first receives, but her strength is in being specially disposed to that reception. It is not a defect in her to be passive in her female role, then, but rather it is a perfection.
Christ’s Blessed Mother personified this receptivity in her fiat, “Let it be done,”{Lk. 1:38) by which she cooperated in the redemption of humankind.
When we say that the woman is the one who receives love in order to love in return, this refers not only or above all to the specific spousal relationship of marriage. It means something more universal…[9]
The receptivity proper to the female principle is not passive in the sense of doing nothing, but is a cooperating in another’s activity. While ordered to generation, it goes beyond generation to inform much more.
Her Individuating Principles
Although the physical differences between the sexes are more apparent than differences in the soul, St. Thomas will further say that even souls are diversified according to sex. Matter is for the sake of its form, he says, and the soul is the form of the body, so if the body is diverse the soul must be also.[10] Nature intends a body to be a suitable instrument, as it were, of its soul. It is precisely because male and female souls are diverse, then, that their bodies are diverse as well.
It may be difficult to say precisely how man and woman differ in their souls. There are certainly many behaviors common to women that are not common to men, and typical differences in the female brain indicate differences in how a woman thinks compared to man. Still these things vary from subject to subject according to more and less, and leave us confused as to the nature of the underlying difference.
St. Thomas gives us a clue at least about what kind of difference sex is.
Since defects of nature are to be repaired in the resurrection, the bodies of those who will rise from the dead will lack none of the things that belong to the perfection of nature. Now, just as other members of the body belong to the integrity of the human body, so do those that serve the purpose of generation, both in man and in woman. Therefore, bodies will rise again with these members.[11]
Though not a specific difference, the sex difference is the kind of inseparable accident that sticks with an individual even into eternity. Sex difference is inseparable due to its “permanent cause”[12] in the subject’s soul. You may look and act like the opposite sex, but you cannot change your sex. You can mutilate your reproductive organs but that which determined them are still written in your unchanging individual principles. Even when your body is decaying in the grave, your soul is still sexed. Sexual differentiation continues into the afterlife because it is part of who you are as a human subject.
The difference which makes a human female is rooted in her individuating principles and ordered to reproduction. We return to our question: What is a woman? I’ll take a stab, though I offer this tentatively as the beginning of a larger discussion. A woman is a human whose individual principles order her to reproduction as receptive.
Conclusion
Even though both man and woman are equally human persons, one’s sex is so much a part of one’s identity that to wish to be a person of a different sex, is to wish oneself out of existence.
And even supposing it were possible, it would be against the natural desire; because there exists in everything the natural desire of preserving its own nature; which would not be preserved were it to be changed into another nature... But herein the imagination plays us false; for one is liable to think that because a man seeks to occupy a higher grade as to accidentals, which can increase without the destruction of the subject, he can also seek a higher grade of nature, to which he could not attain without ceasing to exist.[13]
To be of another nature is to cease to exist. It is something that one can’t really desire, because everything desires to preserve itself. Similarly, one could not change one's inseparable accident without destroying oneself. So what someone is really desiring is to be himself, but with all the advantages that accrue to some other subject. When a man thinks he wants to be a woman, he really is wishing for something he lacks that he perceives women to have. Rather than contributing to the delusion that he can be a woman, the best thing anyone can do for him is to help him both in perfecting himself as a man, and in appreciating himself for who he really is.
It is one thing to be understanding of human weakness and the complexities of life, and another to accept ideologies that attempt to sunder what are inseparable aspects of reality. Let us not fall into the sin of trying to replace the Creator. We are creatures, and not omnipotent. Creation is prior to us and must be received as a gift. At the same time, we are called to protect our humanity, and this means, in the first place, accepting it and respecting it as it was created.[14]