In part 3, Father James Sadowsky answered Murray Rothbard’s assertion that an unwanted, unborn child is a trespassing parasite upon the body of its own mother. In closing his reply to Sadoswky, Rothbard cited an analogy first proposed by Judith Jarvis Thomson in “A Defense of Abortion” (1971).

When music needs your kidneys

Rothbard wrote:

“Suppose that you are kidnapped and find yourself hooked up via a kidney machine to a [violinist] who needs continuous infusion from your kidneys in order to live . . . . Furthermore, to complete the analogy, he only will need your kidneys for nine months, after which he will be unhooked, and there is no danger to your own kidneys or health in the meantime. I say that you would have the right, not merely to unplug yourself from his kidneys, but to be damned “brutal” about it if necessary to get your body out of its enslavement, even if it kills the [violinist] in the process. Would Father Sadowsky say differently?”

One can readily agree with Rothbard that no one should be enslaved in this way, even if it could save another’s life. This is true, even though a voluntary donation such as this would be an honorable and virtuous act. The problem with his analogy, however, is that it has so many dissimilarities from the mother/unborn child relationship.

In the violinist analogy, it is the kidnapped donor who is forcibly drafted to benefit the violinist. In the case of pregnancy, the situation is reversed. The mother is the one who consents to causing the pregnancy (in most cases), and the baby who has no say in the matter.

It may be that the mother does not expressly consent to the conception of a child. She may even be trying to avoid that result, but she is still the person causing the pregnancy, much like a driver who drinks too much alcohol and causes an accident without ever having intended to hurt anyone.

Rather than aiding the pro-choice argument, the violinist/donor analogy is starkly different from the example of a mother and her unborn child. In the violinist/donor analogy, it is the donor who is utterly innocent. The donor has no responsibility for the violinist’s precarious situation, having neither caused it, nor consented to it. In a pregnancy, the roles are perfectly reversed. The mother— rather than being a kidnapped innocent bystander—is a key player and a direct cause of the situation.

Is it OK if I drop this baby?

In the violinist analogy, the kidnapped donor admittedly has no duty to the ailing violinist, but what if the donor had consented to or even caused the violinist’s condition? What if the donor had directly created the situation by pushing the violinist off a building? Is she not a murderer if she then lets the violinist die?

This is a critical distinction because a person can violate the nonaggression principle by placing another person in harm’s way. In the case of abortion, the mother creates a situation whereby the unborn child is completely dependent on her. She conceived the child and placed it in the position that it will die unless she follows through with her pregnancy.

Consider a woman who picks up a baby and holds it. The woman does not ordinarily have any duty to hold babies. But having picked up the baby, may she then drop it to the floor, with the excuse that she has every right not to hold babies? Most will agree that if she drops the baby, she becomes an aggressor and society has every right to prevent her from doing so. The duty to prevent harm falls on the one who creates a potentially harmful situation.

It’s not really about being pregnant

In the violinist/donor analogy, there is also a difference in intent between the donor and the pregnant mother. As noted by Father Sadowsky, the mother’s intentions have less to do with being hooked up to the baby (i.e., being pregnant) than it is to be rid of the baby. To be blunt, the purpose of most abortions is to kill the child, not just expel it. This not the case in Rothbard’s analogy, where the violinist is not directly killed, but only unplugged, to live or die on his own. There is every reason to believe that Rothbard’s unwilling donor would be perfectly happy for the violinist to live, just not at the donor’s time and expense.

In a final distinction between these cases, the mother not only caused her unborn child to be in this life-or-death situation, but she has a unique relationship with the child. Contrast this to the kidnapped “donor” and the ailing violinist, who have no relationship at all.

Abortion in a world without aggression

A pro-life libertarian has compelling moral and legal reasons for treating abortion as a crime, leaving abortion proponents nowhere to hide except behind the pretense that they are not killing a human being. Just as in our world today, abortion— in a libertarian society— will not be ended as long as people disbelieve in the humanity of the unborn child. That leaves pro-life people with the same task they carry on today. They must still change people’s minds about the issue, with the hope that enough people will recognize the humanity of the child and the aggression inherent in abortion. Only then will they accept—as they do with all other violence against persons—that it cannot be tolerated.

There will be progress because even a libertarian-leaning government would be smaller and more locally oriented. Now, with the overturning of the Roe v. Wade decision, this is happening. In many states, where abortion is widely considered to be unprovoked aggression against the most defenseless, abortion is now essentially illegal.

Admittedly, neither education nor punishment will ever stop all abortion. Some abortion may go underground. More likely, some women will travel to legal jurisdictions to obtain one, but none of this is a reason to permit abortion. Such evil cannot be tolerated simply because it cannot be eliminated. While complete abolition is the goal, it will never be achieved, any more than robbery and murder will be abolished.

If a free society acquiesces in such aggression, it undermines its central axiom; but if that same society would relentlessly pursue a non-aggression policy—by protecting even the most helpless—that society secures life and liberty for all.

This series on “Libertarians and abortion” is adapted from Chapter 7 of Free is Beautiful: Why Catholics should be libertarian, available at Amazon in paperback and Kindle versions.