We live in a world of crises. And none is more dangerous than the current crisis of conscience. After all, conscience is, the Pope tells us, “the monitor of true social and moral order.” Without it we lose our bearings, not only individually but socially as well. Since we are social beings even our “private acts” are profoundly social. In many respects, there are no “private acts,” since any of our actions affect our families, our friends, our communities, our nation.

If we are Christians, our “private acts” either strengthen or weaken the entire Body of Christ.

Abortion, which was supposed to be merely a private matter, has had profound social ramifications. A single Supreme Court decision, claiming that abortion was a “private matter,” wiped out many public laws enacted by countless legislators over decades. Since that time our country has been torn apart by controversies over that “private act.” There have been legal and legislative battles. There is the social fact of millions of citizens never born, workers never producing, future teachers, scientists, and doctors never seeing the light of day to make their own unique contributions to society. Ironically there are also those who want the government to pay for that “private act” with public tax dollars. “Private acts” never remain merely “private.”

The Supreme Court is supposed to interpret the Constitution, that document which shapes our life together as a nation. Yet the Court seems so mired in radical subjectivism that it cannot see the necessarily social impact of “private acts.” In Planned Parenthood v. Casey, the justices spoke of the Constitution granting citizens a broad “right to define one's own concept of existence, of meaning, of the universe, and of the mystery of human life.”

The problem of course is that one does not have “a concept of existence, of meaning … of the mystery of human life” without acting on it. The individuals who blew up U.S. embassies in Kenya and Tanzania certainly had their “concept of existence.” Those who kill babies as they are being born through partial birth abortion have their “concept of meaning.” So do scientists who experiment on embryos, and physicians who help patients kill themselves. And so do men in positions of responsibility who exploit women who work for them.

Is it surprising in such a world that even the president of the United States would try to excuse immoral behavior on the grounds that it concerned only his “private life”? Yet we can see how quickly such “private acts” have their social impact, on family, friends, nations.

They even have their implications for national security as we saw when the motives of the commander-in-chief were called into question when he bombed Sudan and Afghanistan.

What is the protection against such dangerous subjectivism? Conscience. It is “the monitor of true social and moral order.” There can be no social order without a moral order. A democracy is only as strong as its citizens and leaders are virtuous. Did our Lord not tell a parable in which a master entrusted his servant with great things precisely because he had been faithful in small things?

Today conscience is falsely understood as the power to do whatever one wants rather than the power to do what one ought. When properly understood conscience tells us how to live for others, not how selfishly to gratify ourselves. Conscience helps us live in accord with our true, God-given nature that was described concisely by the Second Vatican Council: “man … cannot fully find himself except through a sincere gift of himself.”

We can all know what is truly good for us since God created us all with the same human nature. Everyone can know how they ought to act, if they are sufficiently attentive to the voice of God in themselves. Robert Spaemann, a Catholic philosopher, writes: “If there were no such thing as the basic structure of human nature [created by God], whereby certain things are considered reasonable or unreasonable, then the command to love one another would be meaningless and could be replaced by whatever we wanted, for it could be filled with any content.”

This of course is precisely what has happened in our day of “private acts” justified by our “private conscience.” However, even conscience is not really private. It is most assuredly personal. I am the only one responsible for my acts, and I am the only one who will be rewarded or punished for those actions dictated by my conscience. However, one reason we have to answer even for our “private actions” is that none is ever simply “private.”

John Haas is president of the National Catholic Bioethics Center in Boston, Massachusetts.