Freedom is a word that can mean dramatically different things to different people in different settings. The kind of freedom that leads to human flourishing—and that is sustainable over time—is freedom in a much richer sense than what many people mean by freedom today.

Let me take the point even further. True freedom is actually the opposite of what has been called "freedom" at some times and some places. One example from the previous century illustrates what I mean.

The Constitution guaranteed freedom of speech, freedom of assembly, and freedom of religion. I'm not talking about the U.S. Constitution, although the same could be said of it. I'm talking about the Soviet Constitution of 1924. And after that constitution took effect, political dissidents were brutally suppressed; priests, ministers, and rabbis were deported to the Gulag; houses of worship were shuttered; and the press was hammered into line with an iron fist. Lenin, Stalin, Khrushchev, and Brezhnev did all of this even while the text of the nation's constitution proclaimed a paradise of liberty. In the minds of those men, freedom wasn't about the God-given rights of individuals that must be respected by governments. It was about free scope for the will of the proletariat—for whom they were the only legitimate representatives, of course.

This kind of confusion about freedom didn't end with the fall of the Berlin Wall in 1989. Visit almost any major university in America and you'll find individuals praising freedom while admiring ruthless totalitarians, usually without the least sense of irony or awareness of the contradiction. And often the totalitarians being praised are the ones who, while busily stamping out freedom, are reassuring everyone that they're stamping in order to free the people, stamping in pursuit of "national liberty and equality," stamping for "the pacific co-existence and fraternal collaboration of peoples."

Why does all of this matter? When liberty and freedom can mean so many different things—sometimes diametrically opposing things—we are no longer free to have a meaningful conversation about political freedom, at least not until we talk about what exactly we mean when we use these terms.

To some, freedom means nothing more than the license to do whatever they want, when they want—as when a wild teenager longs to be "free of all these stupid rules." To others, freedom means the liberty to worship God freely according to the dictates of their conscience, or the right to govern themselves through duly elected representatives. President Franklin Roosevelt talked about freedom in terms of government-supplied security and even welfare—freedom from want, freedom from fear, and so forth. But the Founders who wrote the U.S. Constitution thought about liberty as limiting what government was allowed to do, and their understanding of freedom was tied up in the old notion of freedom in Christ, which is why they repeatedly emphasized that the constitutional republic they had formed was, as John Adams put it, "made only for a moral and religious people" and "wholly inadequate to the government of any other."

Freedom has a wide variety of meanings—some people think of it as the ability to do what they know they ought to do, even when it is not attractive at the moment, as when a lonely husband remains faithful to his wife while on a business trip, or a recovered alcoholic has achieved enough self-control to live a life of sobriety. For still others, it means what the great twentieth century Dominican theologian Servais Pinckaers called "freedom for excellence," as when a pianist strives to master a demanding piece by Rachmaninoff and is finally able to play it with ease and fluidity.

So let's look at what freedom is and can be. This need not be a terribly abstract and philosophical examination. We can use mon sense and elementary logic. The best of philosophy is looking simply but seriously at things as they really are. Let's begin with what we know, each of us, about ourselves.

I think it can be easily observed that there is something innate in the human heart that responds positively to the idea of liberty— no doubt in more than one sense of the word. People have pledged their lives, their fortunes, and their sacred honor to its defense. Over the course of the last century, countless men and women risked their lives to flee from totalitarian domination into a realm of freedom. People— perhaps even some we have known personally—swam shark-infested waters, climbed electrified fences, catapulted over barriers, dug their way through tunnels, and outran guard dogs and border guards— all to escape bondage and reach a place where they could breathe free. To be aware of what human beings have sacrificed for freedom is to understand that freedom is not a garnish on life but one of the central quests of the human experience. The human heart has a natural orientation toward liberty. We are built this way, regardless of our religion or ethnicity; indeed, all men are endowed with liberty and a deep desire for it.

What is it about freedom that makes it so irresistible a goal—and yet still plex an idea that we can e confused about what it is? Alexis de Tocqueville—perhaps the greatest observer of the uniqueness of America—can help us get a grasp on it. "Freedom is, in truth, a sacred thing," he insists. "There is only one thing else that better deserves the name: that is virtue." And then he asks, "What is virtue if not the free choice of what is good?"

The yearning for freedom is built into our bones. Of course, human beings are corporeal like other animals. We are bodies, subject to the laws of physics, chemistry, and biology. But unlike other animals, the human person has the additional capacity to transcend himself. Even non-believers can observe this aspect of human personhood, for example when a person falls in love and discovers more of himself or herself, even while giving that self away to the other. We also experience this transcendent aspect of the human person in the exaltation we feel in beautiful music, great art, or poetry.

This article is drawn from Rev. Robert A. Sirico's new book, Defending the Free Market: The Moral Case for a Free Economy. (Regnery, May 2012).