Abortion isn’t exactly a “third rail” of American politics, since people yell about it all the time.

But it is a third rail of rational discussion. Many people have dogmatic beliefs about it and they react with blind rage to any heretical disagreement.

The question of who provoked the latest American rage-fest (May 2019) depends on who you ask. Pro-choice partisans say it was state legislatures that passed draconian limits on abortion. Pro-life partisans say it was abortion supporters who finally revealed their true intentions by embracing infanticide.

Each side’s choice of what to emphasize or ignore is dictated by the needs of its argument.

Pro-choice advocates emphasize the mother’s autonomy, arguing — in summary — that:

1. A fetus isn’t a human life and therefore has no human rights.
2. Even if it is a human life, no person can have an unchosen duty to support another person, particularly in her own body.
3. Therefore, any woman can morally get an abortion at any time.

Pro-life advocates emphasize the fetus’s humanity, arguing — in summary — that:

1. A fetus is a human life and therefore has human rights.
2. As a result, abortion violates the fetus’s human rights and is tantamount to murder.
3. Therefore, abortion is a grave moral wrong that can be justified only in extreme circumstances.

Thus, the opposing sides argue past each other. Each tends to ignore or dismiss the other side’s key contentions.

Both sides also see their beliefs as a sign of their own morality and enlightenment. Disagreement then seems like a personal insult, denying their status as good, thoughtful people. Dissent turns into “fighting words.”

Hence, we get screaming instead of argument. Instead of trying to convince people, each side hardens its dogmatic viewpoint and tries to impose it on the other side.

Even if both sides calmed down and tried to discuss the issue rationally, two very tricky problems would remain:

If a fetus is human, that fact by itself doesn’t tell us what to do.

• Biology isn’t the same thing as morality, and it provides no moral rules.
• We need to get the moral rules from some other source.

If neither side can convince the other, then how can we live together in a way that minimizes harm?

• Federalism is one answer: some states would permit abortion, some would outlaw it, and others would take a middle position.
• The democratic process is another answer, but that requires the losing side to accept the validity of democracy. Would it? We can hope.

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