In yesterday’s article, I reviewed some of the ways that philosophical arguments can stand on their own merits, without relying on theological premises, and even enable us to understand religious revelation. So, despite some Christians’ skepticism, they need philosophy.

But what about its value beyond the Church’s life?

For Individuals

First, do natural-law arguments ever persuade?

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Yes. Over the last few years, my coauthors and I have heard from many saying we had convinced them to join the marriage debate by showing them its value (and giving them the moral vocabulary and syntax to discuss it); from others who decided to retire this or that contrary argument; and from still others who switched to our side of the issue. These have included non-Catholics, non-Christians, agnostics, even a prominent former Marxist thinker. We have often remarked, channeling Chesterton, that the argument for marriage has not been tried and found wanting; it has been found (we’d say feared) difficult and left untried.

Then where are the mass conversions? We freely admit that moral philosophy can’t produce them. It doesn’t convert en masse, because evaluating its arguments takes sustained attention. It requires holding several pieces together; discerning subtle patterns; and generating and testing alternatives by turns, in an always-unfinished process. Philosophy is famously better at knocking down than building up; even the strongest of its affirmative conclusions do not overpower but invite, suggest, recommend. And by itself, philosophy tugs so softly at the imagination and senses that it can pull the head before the heart, leaving readers not so much moved as divided.

Note that this is true of any philosophical argument, for any affirmative claim of any substance. That is why we are debating the same questions that faced the pre-Socratics 2,500 years ago—and will go on doing so until the final trumpet interrupts the final philosophy seminar.

This doesn’t mean that philosophy doesn’t matter. It’s a Modern or Rationalist error to think that only philosophy can legitimately motivate, but the same goes for thinking that converting is all it can licitly do. In fact, what makes philosophy a blunt tool for massive campaigns also makes it apt for other ends. For one thing, it can help to keep us integrated—within ourselves and with the truth—when various forces would pull us apart. It keeps us, for instance, from becoming sentimentalists or aesthetes. If your gut tells you one thing and your neighbor says another, you will want to adjudicate the dispute. If a story or social movement sends you riding upon a wave of passion, you might pull back to ask: Is this rage or truly righteous zeal? Pity or true compassion? However informal these interrogations, they will involve the giving and comparing of reasons: i.e., philosophy. Reason is not all that moves a person, but it moves all conscientious persons.

And what is the alternative? Thus again Chesterton:

Philosophy is merely thought that has been thought out. It is often a great bore. But man has no alternative, except being influenced by thought that has been thought out and being influenced by thought that has not been thought out.

And natural law theory is simply the effort to think out moral thought. One will be swayed by moral thought no matter what: the only question is whether it will be well thought out.

For Public Life

One might still wonder what role moral philosophy can or should play in public life.

If abstract reasoning doesn’t convert masses of people, it shapes the thought of those who do—in public and higher education, the media, the arts, and law and policy. Glee may inspire a new generation of sexual libertinism. Yet its screenwriters owe their ideas to late-nineteenth century and pre-World War II thinkers who reduced sexual desire to a brute appetite and the value of sex to the sum of its pleasures. Meanwhile, there may well be a causal chain linking every novel that ever inspired virtue in a young reader to one of the lecture notes of Aristotle. We can’t measure philosophy’s effect, for good or for ill, just by counting how many convert upon reading a tract.

What traditional moral causes need, then, is not fewer philosophers but more of everyone: more artists and authors, poets and playwrights, sculptors and screenwriters to reap the fruits of intellectual work for social ferment. I do what I do not because philosophy alone matters, but because my paintings and plays really would move no one. The next generation of true culture-makers, however, will be shaped purely by bad philosophy, only if it goes unanswered. And it can be answered adequately only by better philosophy.

The same goes for any discipline. If a certain historian argued that Jesus of Nazareth never existed, it would be useless to refer him to the Catechism; only historical arguments would have any hope of curbing his popular influence—through college syllabi or the History Channel or otherwise. Similarly, philosophical arguments about the supposed requirements of justice, equality, and rationality for this or that policy can be answered only in kind. And if they are not, the same arguments will keep shaping makers of culture, and the millions they affect.

In short, too many argue as follows:

Premise: philosophy and policy aren’t enough for our goals.

Conclusion: damn philosophy and policy.

No social conservative—but none—denies the premise. Policies are only a means. Paraphrasing C.S. Lewis, I am happy to concede that all the world’s court cases and white papers add up to nothing in themselves. Marriage laws are for naught unless they facilitate real goods: a child toddling toward his attentive father; a middle-schooler absorbed by her novels instead of grief over her parents’ divorce; a family bickering boisterously over dinner; a young man unscarred by authority, unafraid of commitment, kneeling in prayer, or in marriage proposal. But that’s just the point: as I’ve argued elsewhere and will below, such scenes prevail where good mores and laws (among much else) prevail. They are undermined by the spread of bad ones.

Although Anderson, George, and I have tried to contribute to a good intellectual foundation, we’d be the first to say that our philosophy of marriage needs to be developed and refined, and that the best philosophy alone won’t save the culture. Conservative critics content to remind us of either are wasting energy better spent for a cause we all support.

For the Marriage Debate

Some agree that philosophy matters but suppose that the argument for marriage faces special challenges. They worry that it’s too meaty for a world weaned on philosophies you can tweet.

After all, it requires belief in moral values beyond consent. It requires thinking that some human goods (like marriage) can’t just take whatever shape we wish to give them. And it assumes that human acts (like sexual intercourse) can have natural ends (like reproduction).

Before I go on, I should clarify. My (coauthors’) argument for marriage in no way assumes that it’s generally wrong to frustrate the body’s natural ends. But it does entail that there are natural ends. For it shows that marriage is a comprehensive union of persons, which includes a bodily union, and that what makes for bodily union is coordination toward a single bodily end.

Still, the objection might go, this idea—that the conjugal act unites spouses bodily, because it’s a joint act ordered to a single bodily end—is too Aristotelian, too “enchanted” for modern ears.

Those who reject natural teleology assume something like this: In the modern era, the natural and applied sciences have been spectacularly successful. It took just six generations to get from the first light bulb to the first iPhone. And that success came when hard-nosed scientists dispensed with teleology (Aristotelian “formal” and “final” causes), and just focused on what laboratories can test: material composition, and ordinary cause and effect (Aristotelian “material” and “efficient” causes). Given this modern experience of scientific progress, we should do away with teleology—not just when doing science, but in all our thinking—if we want to be fully rational.

Even granting (for argument’s sake) this assumption about how all scientists operate, one might wonder how the natural world got to be so orderly that the scientific method works at all. I think the deepest answers will appeal to natural teleology. Nor is the concept too “spooky” for belief. Related ideas show up—even today—in countless ordinary judgments: A natural “end” of infants is to become reasoning adults; of flowers, to blossom; of brains, to store memories; of digestive systems, to help nourish. These processes happen not always, nor simply often, but by nature: by natural disposition. Yet that is the sense of “natural end” that marriage arguments require: Coitus doesn’t always lead to procreation, and isn’t just statistically correlated with it. Instead, it is oriented to—begins a process that would be completed by—procreation.

Still, I grant that various factors can block people’s appreciation of this and other natural-law concepts and arguments. We all know that there can be moral obstacles to understanding: Corrupt character can blind us to the moral values being invoked. But it isn’t enough to be morally well trained; there are also intellectual prerequisites for appreciating moral argument.

Alasdair MacIntyre has made much of this point. He argues that everyone reasons from within intellectual traditions developed in particular times and places, by experience as well as reflection. Your tradition in this sense affects the beliefs you start with, the concepts you use, the questions you pose, the possible answers you consider, even the rules of inference by which you move from premises to conclusions. And you can’t reason without drawing on a particular tradition, any more than you can argue without speaking a particular language.

Thus, MacIntyre thinks, if your opponent in debate draws on a different tradition, you must dislodge her from it to win her over. And you can do that by showing her that her tradition creates problems that it cannot solve, raises questions that it lacks the resources to answer—problems and questions on which your own tradition does better. More direct argument than that, MacIntyre thinks, would be as naïve as addressing a Francophone in Kiswahili.

Some MacIntyreans think that my (coauthors’) work on marriage is naïve in just this way. That’s demonstrably false. Whatever the merits of MacIntyre’s broader claims, we agree (as our book’s approach makes clear) that someone plunged in a tradition that rejects teleology must emerge from it if he is to grasp or accept our arguments.

That doesn’t mean that those arguments aren’t accessible to reason, any more than a thief’s numbness to the importance of property makes anti-theft arguments inaccessible to reason. I don’t mean that rejecting arguments is morally like stealing. I mean that, just as practical habits can blind us to moral values that are visible in principle to all, so can intellectual habits—in the use of concepts, claims, and conclusions—make us numb to sound moral arguments.

Some think natural-law arguments useless until the public is better versed in teleological language. This is like refusing to speak Spanish to a student until he’s fluent. Drawing someone beyond the limits of his own tongue is how to make him fluent in another. Avoiding the language of Cervantes until people understand it better is comically self-defeating, but it is what some quite seriously propose to do with the teleological language of Aristotle and Aquinas.

I have no general solution to our culture’s philosophical illiteracy, and I agree we need to work toward one. My point is just that a certain kind of philosophical argument can itself be part of that solution, not the problem. In particular, you can convince someone of teleology—or of objective morality, as opposed to mere taste; or of values besides consent—by showing him that his own views entail these things. Our work on marriage aims to do just that. It shows how the logic of still-shared views on marriage (regarding values of permanence, exclusivity, family life, even romantic love) ultimately requires something like natural teleology, in something like the conjugal view. It shows that common objections to our view—from the basic right to marry, or the value of equality—tend to assume that morality (and the human good of marriage) aren’t just whatever we decide, but have objective structure.

In arguing about marriage, that is, my coauthors and I do just what MacIntyre prescribes. We don’t just lay out our premises, take-them-or-leave-them. We show marriage revisionists that their view creates problems it cannot resolve. MacIntyre writes: “the best defence of natural law will consist in radical philosophical, moral, and cultural critiques of rival standpoints.” That is what our book provides—on the objective shape of marriage as a human good, and (by extension) on natural teleology and objective morality.

But one can agree that philosophy has value beyond the Church and still wonder why we should continue deploying it (or anything) in defense of conjugal marriage. I turn to that tomorrow.