Rethinking Complementarity: From Stereotypes to Icons

The Church’s understanding of men and women is built upon a foundational twofold principle: the sexes are characterized by both equal dignity and meaningful difference. Here is how the Catechism describes this: “Man and woman have been created, which is to say, willed by God: on the one hand, in perfect equality as human persons; on the other, in their respective beings as man and woman” (§369). The Catechism is clear that “man and woman are both with one and the same dignity ‘in the image of God’” (§369); “they are equal as persons . . . and complementary as masculine and feminine” (§372).

This language of “complement” or “complementarity” has come to serve as a helpful shorthand for the Church’s understanding—it is a word that seeks to capture both strands of the twofold principle: equality and difference. Yet there are different interpretations of what “complementarity” actually means, both within a Catholic context, and also across the various forms of Protestantism. I was raised in evangelical Christianity, and in that landscape, there are two primary theories of God’s vision for the sexes: egalitarianism and complementarianism. To put it simply, egalitarianism emphasizes the equal dignity of the sexes while minimizing our differences, in order to argue against sex-based roles in church leadership and the home. Complementarianism, while affirming at least in principle that men and women are equally made in God’s image, amplifies and translates the meaningful difference into distinct roles for men and women and affirms a general hierarchy of men above women, in terms of leadership and authority.

While this particular taxonomy of egalitarianism versus complementarianism emerged in the 80s and 90s in evangelical debates about the sexes, these basic attitudes are nothing new. In fact, they are ancient. We can trace their prototypes back to Plato and Aristotle.

In her panoptic work The Concept of Woman, Catholic philosopher Sr. Prudence Allen offers a sweeping analysis of the various theories or philosophies of the sexes that have developed over centuries of Western thought, categorizing these into the following framework:

As you can see, there are three basic theories at play: unity, polarity, and complementarity. What differentiates these theories is how they hold to or depart from the twofold principle of equality and difference. Unity theories, which we can trace as far back as Plato, emphasize equality while downplaying difference. Polarity theories, which can be seen in many ancient traditions, including Aristotelian philosophy, emphasize difference at the expense of equality, thus affirming a hierarchy of superiority and inferiority between the sexes. Complementarity theories attempt to hold both equality and difference in a fruitful tension.

According to my interpretation of Allen’s analysis, complementarity is a unique product of the Christian tradition—a tradition that affirms on the one hand the shared imago Dei and salvation of both men and women, and, on the other hand, the dignity and redemption of the body. The latter emphasis pushes back against a Neoplatonic unisex vision, in which the body and its sexual difference is an imperfection that must be shed, and the former pushes back against Aristotelian polarity, which, while offering a vision of body-soul union, posits femaleness as an imperfection. Christian revelation, rightly understood, corrects both of these errors, preserving the twofold principle. It has taken centuries, however, for this doctrine of complementarity to develop, and for the errors of unity and polarity to be ultimately excluded from orthodoxy, even if they are still very much around, albeit in modern forms.

As Catholics, then, we want to endorse the theory of complementarity—but as you will notice in Allen’s chart, there are different understandings of what complementarity entails. She highlights two distinct versions in particular: what she terms “fractional” and “integral,” words that rely on a mathematical analogy. Fractions, of course, represent parts of a whole, whereas an “integer” is another term for a whole number.

Fractional complementarity, then, sees the sexes as complementing one another because they each reflect partial or fractional aspects of a whole human being. Fractional complementarity tends to divvy up various human traits and virtues into pink and blue lists: men are more rational, let’s say, and women are more emotional, so together they make up for one another’s deficiencies—together, we account for a well-rounded human being.

Integral complementarity, in contrast, views men and women as whole human persons in their own right. The full range of human traits and virtues is open to cultivation by both sexes. Our complementarity, then, is synergistic—it does not complete a lack but enhances a whole, resulting in a fruitful collaboration that is more than the sum of its parts.

The language of the Catechism clearly endorses an integral rather than fractional understanding of complementarity:

Man and woman were made “for each other”—not that God left them half-made and incomplete: he created them to be a communion of persons, in which each can be “helpmate” to the other, for they are equal as persons (“bone of my bones . . .”) and complementary as masculine and feminine (§372).

Men and women are not “half-made and incomplete” as persons—sexual difference is not ultimately about completion, but about communion, communion that is only possible between two whole persons who are equal in dignity, yet meaningfully different.

But what does “meaningfully different” actually mean? Now that we have established some key guiding principles and categories, here is the question I would like to pursue: at what point does complementarity become “fractional?” To put it a different way: how can we articulate “meaningful difference” without lapsing into a fractional mode, reducing our respective “geniuses” into those pink and blue lists?

Dealing with Differences

At this point, I should probably be honest about something: I have a particular aversion to fractional complementarity. In part, this likely arises from my peculiar background. One of the flaws of fractional complementarity is that it can tend toward a hierarchical view of the sexes, thus masking a hidden polarity. The complementarianism of my evangelical upbringing definitely falls into this mode. Difference was translated into a generalized hierarchy between the sexes, wherein positions of authority and leadership in all or most spheres—including teaching positions—were reserved for men. Certain virtues, like obedience and humility, were often coded as “feminine,” and framed in relation to men, rather than deemed human virtues, oriented primarily in relation to God. For this reason, I am wary—perhaps overly so—whenever something belonging to the sphere of human nature is bifurcated into either a male or female attribute.

I also, however, have an extensive background in feminist theory, which overwhelmingly leans in a “unisex” direction, downplaying differences to emphasize equality. Attempting to endorse or articulate “meaningful difference” between the sexes, without heavily caveating those as patriarchal social constructs, is a major faux pas in academic feminism. Difference, when acknowledged, is assumed to be both artificial and oppressive, something at odds with equality. Yet even in my feminist heyday, I gravitated toward French feminist theory, which, in contrast to Anglo-American feminism, held more space for “sexual difference” and the importance of female embodiment. Even prior to becoming Catholic, I was intuitively grasping toward the Catholic position of equal dignity and difference.

This experience with both polarity and unisex theories places me in an often awkward tension: I want to better understand and articulate the meaning of sexual difference, yet am simultaneously wary of accounts of sexual difference that rely heavily on stereotypes.

That is a charge often levied against the Catholic position, in fact—that it endorses restrictive stereotypes about men and women. So here I want to face this claim, and this tension I feel, head-on. I want to be honest about my own wariness of stereotypes, while also interrogating and testing this wariness, to see whether it holds up to scrutiny.

There are some Catholic accounts of complementarity that I do find overly fractional. These accounts tend to ground complementarity in what I will call “second-order sex differences.” First-order sex differences are differences that are truly binary and true of all men and women. Men have bodies organized according to the potential to produce small gametes and generate through insemination. Women have bodies organized according to the potential of ovulation and gestation. Here, our meaningful difference is stark. Another example of a first-order sex difference might be natural hormonal production. While females produce some testosterone naturally, post-puberty, the female range does not overlap with the male range at all. Here, again, is a stark, bifurcated difference. First-order differences are differences arising from sexual dimorphism that are sharp and distinct.

Second-order differences, then, are fuzzier. Here, I am using this term to refer to psychological or personality-based differences—differences informed by biology, perhaps, but not strictly biological. Unlike first-order differences, these differences do exhibit a fair amount of overlap between men and women. Perhaps the simplest way to explain this distinction is this: second-order sex differences fall along a spectrum with a good deal of overlap; first-order sex differences do not.[1]

Some Catholic accounts of complementarity rely heavily on second-order differences, presenting psychological differences as starkly bifurcated, in order to make the claim that our ability to complement one another is based on binary differences at the level of personality. Men bring one set of traits to the table, and women bring another, distinct set of traits to the table, and thus we make up for one another’s deficiencies—taken together, we are more complete.

A good example of this approach can be found in an essay entitled “Men and Women, Their Differences and Their Complementarity” by Dr. Paul Vitz. He states from the outset a particular understanding of complementarity, proposing “that many of the weaknesses of each sex are matched by a complementary strength of the other sex.” He then proceeds to survey a number of psychological and neurological sex differences—but nowhere does he state directly how pronounced any of these differences are.

The reader is left with the general impression, however, that these differences are polarized and stark, especially as the article culminates in a chart with separate lists of “masculine and feminine psychological strengths and weaknesses”—the list includes some of traits I will be discussing in a moment, such as risk-taking and empathy, listing the former as masculine and the latter as feminine. He then concludes his analysis of all this data with the following statement:

A complementary model allows a fuller understanding of how, taken together, men and women, in their strengths, demonstrate a more complete image of God than does either sex alone. The best way to describe the effects of complementary interaction is with the word “synergy.” The interaction creates much more than what is provided by either the man or woman alone.

While Vitz clearly uses Allen’s language of “synergy” in describing his theory of complementarity, I would say that this statement and his interpretation of the data he presents places him squarely in a “fractional,” rather than “integral” mode.

When we actually look at the strength and size of these differences, a more complex picture emerges, one that belies a vision of complementarity wherein men and women are distinct halves that, together, make up a whole. I am not trying to pick on Dr. Vitz here—I found the research he presents to be quite interesting. I am merely pointing to his article as an example of a particular interpretation of complementarity that, in my opinion, overemphasizes second-order differences.

I would like to scrutinize this approach to complementarity, first by looking at personality differences between the sexes in order to understand where we find meaningful differences, and, perhaps more importantly, how pronounced those differences actually are.

The data I am going to present in this section come from a series of fifteen studies based on a dataset of 15,000 men and women from the U.S. who completed self-assessments on various personality traits. I am not presenting this data as the ultimate authority on male-female differences (there are limits to every study). Rather, I think this data helps illustrate a trend you can see across studies of this type, namely: meaningful but non-polarized difference. Men and women are not opposites when it comes to personality, but neither are we interchangeable.

The researchers in these particular studies examined over 600 traits, and only found statistically significant differences between men and women in eighteen of those traits. Examples of traits from the no-difference list include adaptability, humorousness, dutifulness, self-discipline. The eighteen traits that did reflect a statistically meaningful difference between the sexes are listed here: Improvisational, Unusual, Complexity Seeking, Amicable, Honest, Warm, Forgiving, Aesthetic, Emotionally Aware, Peaceful, Compassionate, Unselfish, Sex-focused, Thick-skinned, Risk-Taking, Self-Valuing, At Ease, Self-Defending.

Importantly, however, even among these traits that reflect statistically significant differences, none of the differences are large—in fact, in the whole series of studies, there were no large differences in the average scores between men and women. (Large here refers to a correlation strength greater than 0.5.)

There is one trait which, among all 600, reflected the strongest correlation to sex: “Sex-focused.” And yet we see that, even in this most pronounced difference, women are closer to the male average 37% of the time, and men are closer to the female average 28% of the time. Again, this was the trait that was most predictive of sex, with the strongest correlation, yet we still have a sizeable minority of men and women that are closer to the average of the opposite sex.

Here is a graph that lists all eighteen of the sex-associated traits, showing the strength of the correlation. Nine of the traits were more associated with femaleness, nine with maleness.

Let’s take a closer look at several of these traits, ones that I would say are more often featured in discussions of complementarity: risk-taking and complexity-seeking on the male side, and emotional awareness and compassion on the female side. Here are screenshots that show the degree of overlap and difference between the sexes, as well as my individual score when I took the test.[2]

There are a number of key takeaways from this data that relate to the topic at hand.

1. There are a number of statistically significant differences in personality traits between the sexes. This pushes back against the idea that men and women are basically interchangeable, i.e. the unisex theory.

2. However, these differences are small and do not at all reflect a stark binary. This pushes back against some interpretations of complementarity that present small differences as if they are large differences—as if our personalities are as asymmetrical as our bodies, i.e. polarity theory.

3. Almost any person will have a mix of results between male-leaning or female-leaning personality traits. Based on my answers to the self-assessment, this model predicted that I have a 75% chance of being female, 25% chance of being male. On the whole, I was closer to the female average. However, there were a number of specific traits where I scored closer to the male average.

4. Moreover, the differences become more bifurcated and pronounced on the extreme ends of the spectrum, not among men and women in the typical range. This is important, because in some discussions of complementarity, the extremes are presented as what is typical of males, or typical of females—whereas, in reality, the typical males and females are the ones closer to the averages of both sexes. This is one of my worries about some articulations of complementarity: small differences are presented as large or stark differences, and thus what is actually atypical for a male or female is presented as typical or representative in general. To put it another way—this means that sex stereotypes are often based on atypical males and females, those who exhibit a more pronounced extreme of a sex-associated personality trait. The female who is closer to the male average (and vice versa) is often presented as the outlier, the exception, when in fact she is closer to the norm.

What, then, are the implications of all this when it comes to thinking about complementarity, particularly about the distinction between fractional and integral complementarity?

To be clear, simply acknowledging, discussing, or studying differences between the sexes does not result in fractional complementarity. We do not need to be afraid to discuss these kinds of differences. However, I believe we veer into fractionalism when a trait that is essentially human is presented as belonging overwhelmingly or even exclusively to one sex or the other. One of the hallmarks of integral complementarity is the claim that our differences, while meaningful and significant, in no way preclude each sex’s ability to develop as full human beings. To put this another way, fractional complementarity arises when second-order differences are assumed to be just as binary and static as first-order differences. That is the first step toward fractionalism.

This leads me to a claim that I am testing out in this essay: while second-order differences such as the ones I have been discussing play a part in complementarity, this shows up at an aggregate level, but not always, or even typically, at the level of individual men and women. Ergo, these differences cannot be the “ground” of complementarity or our respective geniuses, because then a great number of men and women would be exempt from that genius. While analysis and discussion of second-order differences is important and fruitful, our understanding of complementarity should be primarily grounded in first-order difference—grounded, in other words, in our asymmetrical embodiment.

The Ground of Our Genius

Saint John Paul II’s writings provide an excellent resource here for thinking about complementarity first and foremost in terms of embodiment. In his Theology of the Body, when he uses the words “masculinity” and “femininity,” he does not apply these to traits that are abstracted away from embodiment—rather, these terms refer back to the body, to our distinct ways of embodying human nature. Here is how he describes this: “masculinity and femininity” are “two different ‘incarnations,’ that is, two ways in which the human being, created ‘in the image of God’ is a body” (157); “man and woman constitute, so to speak, two diverse ways of ‘being a body’ that are proper to human nature” (179).

Implicit in his words are the two fundamental principles of integral complementarity—equal dignity, as both man and woman are fully human and made in God’s image, as well as meaningful difference, which is manifest primarily in our sexed bodies. It is the embodied person, then, who inflects a trait or an action with masculinity or femininity—it is not the trait per se that is masculine or feminine. Our meaningful difference is not rooted in having differing sets of personality traits—our difference shows up in how these shared traits are embodied and enacted in the world. A man exhibiting compassion is not reducible to a woman exhibiting compassion—not because the trait per se is different, but because that trait is being embodied by a male, and thus takes on a paternal, rather than maternal, character.

Picture, in your mind, an icon of Joseph holding the Christ child. Now picture an icon of Mary holding the Christ child. If we were to describe these two images in terms of abstract traits, we would likely have a lot of overlap—tenderness, love, protection—and yet these images are not interchangeable. They are meaningfully different, irreducible to one another. The difference arises from embodiment. In his Letter to Women, John Paul II refers to this as “iconic complementarity”—our bodies carry an “iconic” meaning, a “powerfully evocative symbolism” that reflects some of the most sacred metaphors in divine revelation. A man can reflect, in a distant but important way, the iconic character of God as Father and Christ as Bridegroom, just as a woman reflects the iconic character of the Theotokos, the God-Bearer, and the Church as Bride.

When John Paul II draws out the significance of our meaningful difference in his Theology of the Body, he emphasizes the sacramental meaning of sexual difference—maleness and femaleness as visible signs of invisible realities. Our distinct bodies carry a nuptial and generative meaning that proclaims the human power to express love and form a life-giving communion of persons. In this way, he writes, man and woman become “the image of an inscrutable divine communion of Persons” (163). Through our sexual difference, in a distant but profound way, we image the Trinity.

Maleness points beyond itself toward femaleness and vice versa; our bodies signal that we are not self-enclosed, self-generating, autonomous monads—we are made for one another. As JPII describes, “the body, which expresses femininity ‘for’ masculinity and, vice versa, masculinity ‘for’ femininity, manifests the reciprocity and the communion of persons” (183). Our sexual difference, then, is a sign of this reciprocal “for,” a sign that we are made for communion and self-giving love, whether that is lived out within marriage or celibacy.

This dynamic of self-gift and reciprocity between the sexes is sometimes characterized (never by JPII) in a fractional way: the man is the “giver” and the woman is the “receiver.” There is some truth to this, but only a partial truth. To return to the body, it is true that in the process of generation the man gives of his own life-giving potential, which the woman then receives within herself in order to make it fruitful. But in bearing fruit, the woman then becomes the giver—the man must receive his child from the woman, he cannot generate within himself. He gives and receives; she receives and gives. The dynamic of gift and receptivity, then, is mutual and reciprocal.

This dynamic is also evident in JPII’s interpretation of the second Genesis creation account. JPII, in fact, first places man in the receptive mode. God is the ultimate giver, and it is he who initiates the dynamic of gift. The man receives the gift of the woman from God, and also receives her gift of self, and then he gives himself in response. It is this reciprocal dynamic of giving and receiving that creates a communion of persons.

On the whole, JPII’s account of sexual difference and complementarity emphasizes mutuality, reciprocity, and self-gift. He is very restrained when it comes to making sharp distinctions between men and women in terms of traits and roles, beyond those that lie in first-order sexual differences, e.g. motherhood and fatherhood. But there is one key area where he highlights a specific call or task that God has placed on the man; it is in this context of the dynamic of gift.

Due to the effects of sin and concupiscence the original dynamic between the sexes has become distorted, disrupted: “the relationship of the gift changes into a relationship of appropriation.” According to JPII, the man, as the first to receive God’s gift of the woman, “ought to have been ‘from the beginning’ the guardian of the reciprocity of the gift and its true balance.” The man has a special responsibility to welcome “femininity as a gift” and to initiate and preserve the “mutual, two-sided” reciprocal exchange between persons. This means actively resisting the effects of concupiscence, the temptation to treat a woman as an object of appropriation rather than a gift.

It is in open conflict with this exchange to take from the woman her own gift by concupiscence. Although maintaining the balance of the gift seems to be something entrusted to both, the man has a special responsibility, as if it depended more on him whether the balance is kept or violated or even—if it has already been violated—reestablished.

The special task or role JPII specifically entrusts to men is to be guardians of the freedom of the gift. Men are called to steward their strength and power into an interior battle against evil, against the effects of sin which distort love into domination. This entails cultivating their own internal freedom, in order to ensure the freedom of women from appropriation and domination.

A special task and mission entrusted to women also comes through in JPII’s writings, a prophetic call that is connected to our bodies and their maternal potential. Whether or not we ever become mothers in a literal, biological sense, our bodies are structured according to the potential to generate a new human life within—to house, protect, and foster a new human life in its most hidden and vulnerable stages. Women who never have children still have bodies characterized by maternal potential and can live attuned to those rhythms. JPII calls women “sentinels of the invisible”—we are the primary guardians of the dignity of human life, especially persons who are overlooked, discarded, unseen.

If the man has a primary role in preserving and safeguarding the dynamic of mutual self-gift and love between the sexes, in receiving the woman as a gift—the woman has a primary role in safeguarding the gift of the child, and protecting this dynamic of love from the threat of domination.

It is telling, perhaps, that the most damaging scandals of our time reflect a violent betrayal of both of these calls: the sex scandals within the Church reveal a perverse and total betrayal of the masculine mission to resist the temptation of dehumanizing sexual conquest; and the culture-wide embrace of abortion under the guise of protecting women’s rights is a betrayal of the feminine mission to safeguard the sanctity of hidden human life.

This understanding of complementarity—of our respective missions in the world, based on the prophetic call of our embodiment—truly reflects an integral vision, a vision of men and women as whole persons, which includes our freedom to respond to this call. Our meaningful difference, rooted not in abstracted, polarized traits, but in the genius of our bodies, presents to us a mission and a task—one we can choose to accept or reject.

Fractionalism tends to view differences as static, fixed, as if we are pre-programmed to think, feel, and act in two polarized modes. But any truly Catholic theory of complementarity must include an emphasis on human freedom and moral agency; even if we are responsive to and influenced by biological and social forces, we are not wholly determined by them. We are not machines. We are animals, yes, but moral and rational animals, capable of self-shaping choices and acts, particularly when cooperating with divine grace.

Authentic masculinity, then, is not about exhibiting male-typical personality traits or embodying a stereotype; it is living and embodying holiness as a man. Authentic femininity is not about ticking off boxes on the pink trait list. True femininity is to manifest holiness as a female human being. It is holiness that makes our sexual difference truly iconic, enabling our visible bodies to proclaim what is invisible, to reveal the glory of God—the man and the woman who are fully alive.

EDITORIAL NOTE: This article is adapted from a plenary lecture at the McGrath Institute’s conference, “True Genius: The Mission of Women in Church and Culture,” on March 27, 2025.