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Let’s Think About Sex

Is there a natural design to sex that we ought to reverence?

In his book Society and Sanity, Catholic theologian Frank Sheed makes a bold claim: “The typical modern man practically never thinks about sex.”

I know what you’re thinking: “How can you say modern man doesn’t think about sex? Just watch the commercials—from shampoo to yogurt to cleaning supplies, everything is sexualized. Haven’t you heard of Fifty Shades of Grey?”

I haven’t read the book or seen the movie, and, yes, everything in our culture is hyper-sexualized. But this is not thinking about sex. As Sheed explains:

[Man] dreams of it . . . he craves for it; he pictures it, is stimulated or depressed by it, drools over it. . . . [But] this drooling is not thinking, picturing is not thinking, craving is not thinking, dreaming is not thinking. Thinking means bringing the power of the mind to bear: thinking about sex means striving to see sex in its innermost reality and in the function it is meant to serve (Society and Sanity, 107).

What Sheed is getting at is this: to think about sex is to ask, “What is it for? What are the intrinsic purposes of our sexual powers? Is there a natural design to sex that we ought to reverence?”

The good and the bad

These are important questions, because what is good for a living being is determined by the ends or purposes for the sake of which its natural faculties exist. For example, the roots of an oak tree exist for the sake of providing the tree with nutrients and stability. Anything that frustrates the achievement of these ends, such as tree poison, would be bad for the tree—that is to say, it would impede the tree from being what it’s supposed to be, given its nature. And notice this judgment is independent of what you or I think about trees.

By contrast, anything that helps the tree achieve these ends—water, fertilizer, sunlight—is good for the tree; that is to say, it will help the tree flourish. And notice once again our judgment about what is good is independent of what you or I think. It’s an objective fact.

Human beings are no different from other living things in that we have a nature or essence with characteristic faculties for the sake of pursuing certain ends, the achievement of which is perfective of human nature. For example, besides the faculties and capacities that we share with the animal kingdom (e.g., sight, hearing, digestive system, sexual powers, etc.) we have faculties unique to us as rational animals—namely, intellect and free will.

The intellect by nature is ordered toward knowing the truth inasmuch as the truth (being as known) is the proper object of the intellect, and thus knowledge of the truth is good for human beings. Your reading of this article testifies to this.

The free will by nature is ordered toward free actions; this has as its proper object the universal good (being as desired). Therefore, to decide freely, without coercion, which belief you will choose to embrace after reading this article is a good thing for you as a human being.

The sexual good

The same line of reasoning applies to our sexual faculties. As philosopher Edward Feser writes, “For if what is good for us is determined by what realizes the ends inherent in our nature, then what is good for us in the sexual context can only be what realizes the ends of our sexual faculties” (Neo-Scholastic Essays, 387).

Therefore, if our sexual faculties exist for the sake of certain ends, and as rational agents we naturally possess these sexual powers that we might pursue these ends, then it cannot possibly be good for us to use our sexual faculties in a way that prevents the realization of these ends.

Now, it belongs to our rational nature to do what we perceive to be good (Summa Theologiae, I-II:94:2), and the good within a sexual context is the achievement of those ends for which our sexual faculties exist. The rational person, upon perceiving those ends, will behave in a way that facilitates their achievement and avoid behaviors that will actively frustrate them. In short, to be rational means doing what is good and, in particular, doing what is good in the sexual context.

So, what are the ends or purposes of our sexual powers, the achievement of which is constitutive of our human good? In other words, what does nature intend for human sexuality?

What’s pleasure got to do with it?

Someone might say, “Sex is meant to express love.” I would agree. However, as Thomas Aquinas teaches, “love is to will the good of another.” So, we’re right back to the question of what sex is for, since its natural purposes determine what is good for us with regard to sex.

“Okay,” says the inquirer, “the natural purpose of sex is pleasure.” Although sex involves pleasure, and this may be a subjective motive for having sex, it doesn’t stand up to scrutiny as nature’s ultimate goal for sex, and thus it can’t be that which is the measure of reasonable sexual activity.

For starters, one can attain sexual pleasure in many ways:

  • A man can rape an unconscious girl whom he drugged at the bar.
  • A doctor can sexually abuse a patient in a persistent vegetative state.
  • As one woman said in an on-street interview that Catholic Answers conducted, “Someone could marry their donkey for all I care”— which, of course, implies certain types of sexual behavior with the donkey.

Anybody of good will recognizes that such behaviors are not appropriate human sexual behavior. Therefore, there must be something other than pleasure that makes for proper sexual activity—that’s to say, sex must be for something other than pleasure.

Moreover, pleasure is not the ultimate purpose of sex any more than pleasure is the ultimate purpose of eating. Eating is pleasurable, but it’s clearly not for pleasure. Pleasure is subordinate to the intrinsic purpose that eating serves: nourishment of the human body.

The same line of reasoning can be applied to sex. When we bring the power of reason to bear on our sexual powers, we see that sexual pleasure is subordinate to the end (goal) for which nature intends humans to engage in sex: to reproduce.

The “baby-making” meaning of sex

In his book On the Meaning of Sex, philosopher J. Budziszewski identifies two conditions that must be met in order for some end to be the purpose of some faculty, and the procreative end meets both of them.

First, it must be the case that the faculty actually brings about the end. Do male and female sexual organs actually bring about children when used in genital union? Yes, given there are no accidental or natural impediments.

Second, the end must explain why we have the faculty in the first place. Does procreation explain why humans have sexual powers? Yes. Without the begetting of children, our sexed bodies would be unintelligible. To put it another way, if we weren’t meant to reproduce we wouldn’t have sexed bodies. Nor would our species be around for long.

That’s not to say that procreation entails sex, since there are some species that reproduce asexually. Rather, the claim is that sex entails procreation. Procreation is that for the sake of which sex exists. Even if conception doesn’t occur in a particular instance, the act itself is still procreative in kind: it’s still naturally ordered toward its end. The accidental failure for the act to achieve procreation no more nullifies its natural purpose than a professional baseball team’s loss of a game nullifies the franchise’s purpose to win.

Regardless of what man may use sex and his sexual powers for—whether the expression of romantic love alone or the giving of bodily pleasure in recreational activity—childbearing is sex’s intrinsic purpose. It is the end toward which sex is ordered.

Where’s the love, man?

At this point an objection abounds: “Karlo, aren’t you reducing sex to mere biology and mechanics by saying sex is for begetting children? Your position seems to suggest that human sex is no different than sexual activity among the brutes.” If I may give the interlocutor the voice of Mater, the hippie van from the animated movie Cars, “Where’s the love, man?”

Although the procreative dimension is constitutive of our human good since it belongs to us as rational animals, the charge that such a view reduces human sex to mere biology might have force if producing children were the end of the story. But it’s not. There is another purpose of sex intrinsic to making babies: the physical and emotional drawing together of spouses. This is called the unitive end or purpose of sex.

There are two ways to see this intrinsic connection. The first sees the spousal friendship as finalizing the procreative dimension inasmuch as the union between the mother and father is needed for proper rearing of the children.

Unlike some species in the animal world, human infants cannot care for themselves. Nature has ordained them to be radically dependent on others for their needs, and for a long period of time.

The needs for human offspring go beyond the mere physical. Because humans are rational animals, children also depend on others for what Aquinas calls “the training of the soul” (Summa Contra Gentiles bk. III, ch. 122). Children’s minds need to be formed in what is true. Their wills need to be directed toward what is good. They need help in learning how to live in community with others. (Being a father of five, I can attest to this).

It’s here where the union between husband and wife comes into play. Nature ordains that both man and woman be needed for the child to come into existence and to be reared. It’s difficult for a mother to protect and provide for herself and her children when she is pregnant and/or attending to the needs of her offspring. So, naturally, a father has to provide for and protect the woman and their children. Both parents are also needed to bring their children to full, healthy maturity as members of the human race.

Unlike animals

There is another way that spousal friendship finalizes the procreative dimension. It does so inasmuch as it makes sex a human reproductive act.

The natural end of begetting children follows from the animality of human beings. It is our sexed bodies—our reproductive organs—that order sexual activity toward procreation. We have this in common with other animals.

But we know that human sexual activity is different than animal acts of reproduction. No one in their right mind refers to dogs as “making love.” Mares don’t don lace nighties to enhance the equine sex experience. Ranchers don’t dim the barn lights and put on Barry White music for their cattle to breed.

So, what is it that transfigures reproductive acts for human beings and makes them distinct in the animal kingdom? What is it that makes sex properly human? We can begin to glean the answer by considering other human acts.

Let reason be your guide

Take the act of eating. All animals share the drive to eat for the sake of self-preservation. But far from being purely an animal activity, eating for humans is infused with rationality.

I’m sure at some point in your life, at least if you’re a male, while sitting at the dinner table, your mother scolded, “Son, where are your manners? Stop eating like a pig. You weren’t raised in a barn.” Such a reprimand implies that there exists a standard of eating that elevates the animalistic inclination to that which is appropriately human. That standard is reason.

Human sex is more than animality

What this example shows is that our animal sentience become human only when integrated with our rationality. This also applies to sex.

For sex to be genuinely human, it must be integrated with our rationality, which involves knowledge and love. And where is knowledge and love united but in friendship or interpersonal communion? The bodily union between man and woman that is ordered to begetting children therefore finds its human perfection in what Thomas Aquinas calls the “indivisible union of souls” (Summa Theologiae III:29:2) that exists between spouses.

We might say that the unitive dimension of sex is to the procreative dimension what the rational soul is to the human body. Just as the rational soul makes our bodies human bodies as opposed to animal or vegetative bodies, the spousal friendship (communal living) makes our procreative inclinations properly human, integrating them into the rational part of our human nature. So, once again, the unitive end of sex flows intrinsically from the procreative.

Violations of the sexual good

Given what was said earlier about what constitutes the good and the bad and the ends for which our sexual powers exist, one can see how any sexual behavior that would involve frustrating the achievement of any one of these ends is not good for us as humans.

For example, sexual behaviors that traditionally have been seen as deviant, such as sexual activity between members of the same sex, masturbatory acts, bestiality, and contraception all actively frustrate the procreative end of our sexual powers. They also thwart the unitive end as well.

Masturbatory acts take sexual arousal toward a climax that doesn’t involve another person, thus turning it in on itself. Bestiality orders sexual arousal toward an object that is not a person. Homosexual acts order sexual arousal toward a person but of the wrong sex. Contraception frustrates the unitive in as much as it robs the sexual act of the power to express the love it was meant to express in the first place. If love is to will the good of another, and contraception is not good, then a contraceptive act can’t be an expression of love.

Other sexual behaviors can be seen as not good as well. Fornication threatens to bring a child into being without the stable spousal union that child needs for proper rearing. Adultery threatens the stability of that union. So-called sex change doesn’t just frustrate the end of procreation but mutilates a healthy organ, rendering it defective. This is no different than destroying a healthy eye by rendering it blind.

It’s because these behaviors are contrary to the good of human beings, and thus contrary to human flourishing, that we should in no way approve, promote, or celebrate them—whether personally or through the court of law.

I reject nature

Now, you might be thinking similar thoughts to the character Skipper in the animated movie Madagascar Penguins: “You know what? I reject nature.” What’s interesting is that we have the ability to do this in some sense—that is to say, as free agents we have the capacity to act contrary to our nature and the ends for which our faculties exist. But should we do this? Here are a few things to consider in closing.

First, it belongs to us as rational beings to pursue what is good for us given our natures. And since the good in the sexual context is to use our sexual faculties in a way that is consistent with the ends of procreation and union, then we ought to use them accordingly and avoid any behaviors that would be inconsistent with these ends.

Second, what’s good for us is perfective of our human nature and thus constitutive of proper human happiness and fulfillment. If we want to be happy, then we ought to reverence—that is to say, live in close harmony with—nature’s design for human sexuality.

Third, if we divorce our evaluation of human sexual behavior from nature’s blueprint for sex and say it’s okay to actively frustrate the achievement of at least one of the ends for which our sexual faculties exist—namely, procreation—then logically we must say it’s okay to actively frustrate the achievement of the other—namely, union—and every other aspect of sexual activity that flows from these two ends, such as consensual sex, permanency, and exclusivity. Such logic justifies any kind of sexual behavior.

Fourth, the logic that justifies actively frustrating the achievement of the ends of our sexual faculties justifies frustrating the achievement of the ends of other faculties. For example, in principle there would be nothing wrong with actively frustrating man’s end to know the truth, as is the case with lying or intentional withholding of education.

There would be nothing wrong with actively frustrating the end of free will, namely, free consent. This means no one could reasonably argue that consent is necessary for appropriate sexual behavior, for to do so would be to concede that we can’t actively frustrate the ends for which free will exists. But if we must reverence free will’s end in evaluating sexual behavior, then why not the procreative end of our sexual powers?

Finally, if one thinks our natural ends or the proper functions of our natural faculties have no moral significance, or are irrelevant, then one must conclude that reason’s natural purpose of providing sound arguments for a belief is irrelevant. But this undermines any argument in support of the deviant sexual behaviors mentioned above. If reverence is due to the natural end of reason, then reverence is due to the natural ends of sex.

The bottom line is that reason says “no” to the deviant sexual behaviors mentioned above because reason says “yes” to what’s good for us as human beings. If we want to be happy, we should let reason be our guide.

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