But it's more than just bad government-it's bad for my children. It's bad for them because pushing the Ten Commandments as a moral code is bad ethics, bad religion, and bad psychology. Here's why:

1. They conflict with one another.
We're commanded not to kill and not to lie. But what if the only way to prevent the killing of a person is to tell a lie? Or to steal? The Commandments by themselves offer no help in resolving such conflicts. To resolve them, you must appeal to moral principles that are outside the scope of the Commandments.

2. They are too vague to be useful.
We're commanded to "honor thy father and thy mother." Does this apply even when the father abuses his children or batters his wife? It's not clear. We're commanded not to kill. Does this mean we cannot kill in self-defense? That we cannot kill to save lives? The 10 C's are fuzzy. And to unfuzz them you have to interpret them by appealing to a moral theory.

3. They are inadequate.
Can the Ten Commandments guide us in making the toughest moral choices of our lives? Can they tell us what our moral duties are regarding capital punishment, racism, gay rights, women's rights, overpopulation, artificial insemination, and the rationing of health care? The 10 C's moral code is no more enlightening in such cases than a restaurant menu.

4. They are absolutist to the point of being immoral.
Like some secular systems of ethics (Immanuel Kant's, for example), the Ten Commandments admit no exceptions. Thou shall not-regardless. If a man has starving children and the only way to feed them is to steal food, he must not steal, even if his children die. A code that sanctions such acts is immoral. Those who try to stick to absolutist codes are like moronic hikers who walk off a cliff because they were told to stay the course.

5. They have no divine authority.
The Ten Commandments are presumed to have divine authority. To many, this means that certain acts are right or wrong because God says they're right or wrong. That is, God is the author of morality; there is no morality independent of God's commandments. If God had not said that adultery was wrong, it would not be wrong. But if this were true, then God could just as easily have commanded that we go forth and murder our mothers, rape our neighbors, and rob our friends. And God's saying that these actions are right would make them right. But this is absurd. Clearly these actions would be wrong regardless of what God commanded.

6. There is no evidence that they work.
Posting the Ten Commandments is supposed to change people's behavior. Teens will stop shooting teens. Drug abuse will wane. This is an empirical claim that can be tested scientifically. Trouble is, there is no evidence at all for this claim. Commandment supporters say that, when prayer and Bible-reading were in the schools, morality was higher and crime was lower. Critics reply that, when God was in the schools, racism and gang wars were up and tolerance for religious minorities was down. Fact is, such correlations are not well established, if at all. And even if they were, correlations are not the same thing as cause and effect. If they were, we could plausibly claim that religion causes school shootings since most of the recent high-profile school shootings involved assailants who were religious.

Worse still, posting the Ten Commandments in school is likely to cause conflict because they are partisan. There are several versions-Protestant, Catholic, and others-each based on a different dogma. There is no "standard" version, as George W. Bush recently suggested. Whose version should get posted? Fight! Fight!

7. They give children the wrong message about morality.
I want my teenage children to understand that there's more to being moral than trying to adhere to simplistic rules. Life is more complicated than that and so is morality. I want them to see that there is such a thing as objective morality-but that morality can't be put on a bumper sticker. I want them to learn how to work from an overriding moral theory that makes sense of moral principles and helps resolve conflicts among them. I want them to be mature enough to reject ethics that fly in the face of our considered moral judgments. I want them to do the right thing because they have empathy and understanding of what's at stake-not because dogma compels them. And I want them to make good choices and take responsibility for every one of them.

Lewis Vaughn is the Editor of Free Inquiry.