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Presenting the pro-life case to libertarians, and the libertarian case to pro-lifers

The “Right” of Abortion: A Dogma in Search of a Rationale

Abortion seriously divides libertarians. This article will examine the arguments of three libertarians who support abortion as a legal right: Walter Block, Tibor Machan, and Murray Rothbard. 1 None of them advanced a case for this alleged right.
Whether the unborn are “persons”, in the sense of human beings entitled to legal rights and immunities, pervades the debate on abortion. Rothbard claims, however, that “trying to define the exact point at which human life begins … bogs the argument down in biological technicalities” irrelevant to the legal issue. He adopts the position that, even if the unborn are human beings entitled to rights and immunities, they suffer no deprivation of these through abortion. If the unborn are not persons, though, further investigation is unnecessary, since only persons can have legal relations with other persons. To determine whether the unborn are human beings is, therefore, relevant.

Tibor Machan

Machan asserts that an unborn individual is only “a human fetus or a human embryo”, not “a full-fledged human being or person”. This dichotomy rests on his definition that a “human being or person is an animal with at least the latent capacity for rational thought and choice” and on the contention that the unborn, “until late in their development”, have only “the potential” but not the capability for such thought and choice.

The problems with this line of argument are several and serious. First, Machan never justifies his definition of a person.

Second, he never distinguishes “latent capacity” from “potential”. The adjective “latent” is crucial. Even if the capacity of an individual (what he can do now) is different from his potential (what he can do later), how does “latent capacity” differ from “potential”? An individual cannot have a latent capacity to do something unless he has the potential to do it, and vice versa. The qualification “latent” retains within the category “human being or person” individuals temporarily incapable of “rational thought and choice” because asleep, unconscious, or intoxicated. The adjective vitiates the distinction, however. For it would not strain language to describe a comatose or intoxicated individual as potentially capable of “rational thought and choice” — that is, capable if his biological mechanisms overcome trauma or purge toxins from his system. And if these temporarily incapacitated individuals are “persons”, entitled to rights, because their bodies can restore them to a wakeful condition, why are not the unborn similarly entitled, since their innate biological processes (absent disease, accident, or intervention) will inexorably empower them to engage in “rational thought and choice”?

Third, Machan nowhere defines “rational thought and choice”, although he makes the existence of human rights and immunities depend upon this criterion. Neither does he indicate who decides what constitutes “rational thought and choice” — that is, who judges the humanity, and capacity for rights, of other individuals.

By leaving such conundrums unresolved, Machan provides a rationale for elitism: To those individuals who consider themselves uniquely capable of “rational thought and choice” there is nothing novel in the notion of a class of beings specially privileged to rule others according to criteria invented by themselves. Prior to the Civil War, it served as the main prop in the “positive-good” apology for Negro chattel slavery; under the Nazis, it appears in the Herrenvolk theory; and, for contemporary communists, it rationalizes the oligarchy of their “vanguard party”. What is novel is Machan’s implication that elitism comports with libertarian principles.

Murray Rothbard and Walter Block

Block and Rothbard avoid the pitfall of elitism by admitting or assuming for purposes of argument that unborn individuals are persons entitled to rights. But they deny that abortion abridges these rights. Rothbard considers the issue trivial. No one, he argues, will make the “absurd” contention that “a full, adult human being has the legal … right to remain enclosed within the body of another human being without the latter’s consent…. But if no adult human has such a legal right, then a fortiori, the fetus cannot have such a right either.” Why “a fortiori”? The term “a fortiori” implies that, because one conclusion is valid, therefore another that it subsumes, and that is less improbable or unusual, must also be valid. Yet what is more improbable than “a full, adult human being … remain[ing] within the body of another”? And what is less unusual than an unborn individual gestating in its mother? Indeed, the most likely presumption from the biological facts would be a right in the unborn to remain within their mothers, and an absence of right in adults to reside in other people’s bodies — that is, different legal relations in the two dissimilar cases, not an “a fortiori” similitude, as Rothbard claims.

From inapt analogies, Rothbard turns to question-begging. “What human”, he asks rhetorically, “has the right to remain, unbidden, as an unwanted parasite within some other human being’s body?” Now, as a matter of biology, the unborn are not “parasites”, since the host-parasite relation can exist only between different species. Neither is it appropriate to label them “parasites” in a legal sense, absent proof of that status independent of its mere assertion. To say that the unborn are “parasites” in a legal sense implies that they have no immunity from abortion. But that is the very issue presented for decision, not an accepted premise of the argument.

Rothbard also argues that, even if the mother “originally wanted or at least was responsible for placing the fetus within her body”, she may, “as the property owner in her own body … change her mind and … eject it”. For, he says, “every individual has the absolute right to own, to control … her own body”. Block agrees. “[C]ontinued unwilling pregnancy is a violation of the mother’s rights to her own body” and therefore a form of slavery. The argument that abortion is legitimate because a woman has a privilege to control what is biologically her own body, however, begs the question of what rights a woman has to endanger someone else’s life through her actions. Every person has a privilege to control his own body only in so far as that control does not result in aggressive injury to another human being. Rothbard and Block simply evade the issue, therefore, when they defend abortion on the ground of “woman’s property rights”. If, as they concede, the unborn individual is a person, entitled to rights, to the extent of those rights he cannot be entirely defenseless against his mother’s use of her own property to threaten his life.

Rothbard attempts to bolster the “property” argument with ideas drawn from his curious “will theory of contract”. Abortion is legitimate, he claims, because to deny a woman the privilege to change her mind about continuing a pregnancy would amount to “alienating her will”, thereby enslaving her. Why a person’s will is inalienable, however, he never explains. Nor could he. The entire system of contract and property which libertarians take for granted depends upon exactly the opposite of what Rothbard asserts: namely, that once a person has taken appropriate steps to transfer property to another, his control over that property ceases, never to return by unilateral willing on his part. If one element of “property”, in the legal sense, is the ability of the owner to project his will upon material objects in order to control their use and disposition, then transfers of property must entail alienation of one’s will with respect to the property transferred. Moreover, there is no self-evident reason to exclude from this result the property one has in his own person.

Rothbard and Block defend abortion on the basis not only of purported property rights in women, but also of absence of rights in the unborn. The victim of an abortion, says Block, suffers no deprivation of rights because, although “[t]here are rights to liberty, and to the pursuit of happiness, … there is no ‘right to life’ itself”. “[E]very right” continue Block, “implies an obligation. If anyone has a right to life, then everyone has an obligation to keep that person alive.” And this both he and Rothbard deny. “[N]o human being”, the latter declares, “has the legal right to keep itself alive at someone else’s expense. No human being can have a legal claim upon someone else to perform any actions to keep it alive.” Surely the notion that there is no “right to life” would surprise people schooled in the teaching of the Due Process Clauses of the United States Constitution. But this is only because Block and Rothbard use the term in its socialist, not its libertarian, sense.

The classical-liberal right to “life, liberty, and property (the pursuit of happiness)” are rights — or, more properly, immunities — which run against government. They limit the authority of government to deprive an individual of these values, or to fail to protect him in their enjoyment; but they do not impose a duty on any public agencies or private citizens to provide opportunities, wealth, or other material amenities of life. In short, Block is wrong. There is a “right to life”: the right not to be killed by an aggressor. Indeed, that right precedes all others. How could one claim rights to liberty and property if others could deprive him of life itself at their discretion? On the other hand, there is no right to be given life. But neither are there rights to be given liberty, in the sense of opportunities the market withholds, or property, in the sense of material wealth others prefer not to transfer. Abortion, however, does not involve giving life, but taking it. The unborn individual has already received his life through the natural process of conception. Those whom Block and Rothbard defend wish, through medical intervention, to deprive that individual of what he now has. To say that they may do so because the unborn has no right to life begs the question of what his rights are.

Admittedly, there is no socialist “right to life”, no general right to demand that others supply the means of one’s existence. But Rothbard is wrong to claim that no one can have a particular right to keep himself alive at someone else’s expense or through someone else’s actions. Such rights would be enforced every day in any libertarian society. For example, if through negligence a motorist seriously injured a pedestrian, the law would require the motorist to pay money damages measured by the medical bills incurred, to keep the injured person alive. Or, if the motorist were a medical doctor, the law would require him to perform appropriate emergency actions at the accident scene to save the life of the person he injured. Or, the law might require motorists not to use their property in certain ways, such as moving at high velocity through school zones, so as to protect the lives of others. Each of these cases, however, involves a situation in which one person is kept alive or protected from fatal injury at someone else’s expense or through someone else’s involuntary actions. In terms of the legal principles involved, then, there is nothing radical in the position of those opposed to abortion who argue against any privilege in a woman to take actions that will necessarily result in fatal consequences to her unborn child.

Block and Rothbard go beyond a mere negation of the unborn individual’s right to life, however. Block argues that “each person is sovereign, owing nothing not voluntarily agreed to (except, of course, for the obligation not to initiate violence, which applies to each of us whether or not we have consented)”. He never explains, though, either why a person is bound — and how he is bound — to accept that non-aggression principle even without consent; or on what ground that is the unique involuntary obligation. Surely the non-aggression principle does not rest on the ground asserted by Block, that “each person is sovereign” — for a truly “sovereign” person operates under only such obligations as he willingly assumes. But even if Block is accidently correct on this point, it does not advance his case for abortion.

If an unborn individual is a person, entitled to rights, he is entitled to the right to life (in the libertarian sense). This right implies a correlative duty on the part of all other persons not to take his life, except in two cases: first, if the child commits aggression against the life of another person; and second, if the continued lives of the child and another person are mutually incompatible because of existential circumstances beyond their control. The first case raises the privilege of self-defense, which permits a victim of aggression to protect his own life, even if that protection requires taking the aggressor’s life. The second raises the privilege of self-preservation, which permits an innocent individual to take the life of another innocent individual in an “emergency situation in which both cannot survive and the survival of one depends upon the denial to the other of the means of survival. The question Block does not answer is whether abortion comes within either exception to the duty of each individual to respect and preserve the life of every other person.

Abortion is not an exercise of the privilege of self-defense unless the unborn child is an aggressor. Aggression requires either an act of will or an act of negligence on the part of the alleged aggressor — for it is hardly just to hold an individual responsible for the consequence of existential forces beyond his control. Aggression does not exist if human action, in the sense of purposeful behavior, is not involved at all. Now, his own creation is not a purposeful or negligent act of the unborn child, but is rather the inexorable result of biological forces independent and beyond the control of the child, and brought into play by the acts of others. Therefore, since the unborn individual is not responsible for his own creation, he cannot commit aggression by coming into — indeed, being brought into — existence. But, since an unborn individual is not and cannot be an aggressor against anyone, how can his mother invoke the privilege of self-defense against his continued existence in the one place in which, at this stage in his development as the human being, it is both logically and biologically appropriate for him to be?

Similarly, abortion is not an exercise of the privilege of self-preservation unless the pregnancy endangers the lives of both the unborn child and the mother. The privilege of self-preservation applies only in those “lifeboat” situations wherein the lives of two and more innocent persons are in jeopardy, and not all can be saved. But pregnancy is not such a situation in the normal case, the case that both Block and Rothbard claim is appropriate for abortion. (Of course, were an extraordinary pregnancy a “lifeboat” situation, the mother would have a privilege to defend her own life through abortion or to choose to give up her life to save the child, if possible.) In sum, Block’s own theory that pregnant mothers must accept the obligation not to initiate violence leads to a conclusion exactly the opposite of that he advances.

Rothbard tries to sever Gordian knots of this kind through semantic legerdemain. “Abortion”, he advises, “should be looked upon not as killing the fetus but as ejecting it from the mother’s body. The fact that the fetus might well die in the course of the ejection is incidental to the act of abortion”. The techniques employed in contemporary abortion operations, however, prove beyond a cavil that the death of the unborn child is the very purpose of what Rothbard euphemistically styles “ejection”. In most cases, the death of the child is caused before, rather than during or after, ejection; ejection is usually a consequence of the child’s death and not vice versa. This fact is vital, since intent is an important criterion in law for distinguishing innocent from criminal homicides. No one can seriously argue that a landowner could successfully assert in defense of a criminal charge that the death of a trespasser whom he had hurled from his property by means of a shredding machine should be considered merely “incidental” to the act of “ejection”, and therefore not an unlawful killing.

Block, however, suggests that bothering to define the rights of the unborn is unnecessary in any event: “Since fetuses are dependent on the owner of the womb in which they reside, they derive their status from that owner’s attitude toward them…. A guest may be asked to leave. A fetus may be removed.” Block admits, though, that one person may not invite another for a ride in his airplane and then, at high altitude, revoke the license and expel the passenger. “No”, he says, “this would be fraud at an almost ludicrous level.” But why is Block’s passenger not completely dependent for his “status” on the plane’s owner? The passenger has a right not to have his life jeopardized by another person’s fraud, yet he chose not to protect himself against fraud, and to expose himself to the consequences. Conversely, an unborn individual has no ability to protect himself against anyone, and no choice but to expose himself to the continued good will of his mother — being, after all, the mother’s captive. If Block can invoke fraud as a deus ex machina to save his passenger by requiring the pilot to return him safely to the ground, why cannot those opposed to abortion also successfully argue that a created person has, by his creation in a state of dependency, a right to be preserved and protected by his creator until the creator can transfer that duty by contract or waiver either to another protector or to the created person himself?

But an even more interesting problem lurks in Block’s theory of “status”. If an unborn individual derives his “status” from his mother’s attitude towards him, he also derives his personhood and rights therefrom. For, if his mother may destroy him before birth at her discretion, he can become capable of exercising rights only through her sufferance. Why, then, may not mothers argue that they confer rights on children they bear only contingently — that, in short, they reserve some or all of the absolute power they wielded before birth to limit their children’s rights as they (the mothers) see fit at any time? Under common law, after all, if one person has the discretion to confer rights or privileges on another, he may normally condition such rights or privileges as he grants in whatever manner he likes. Most likely, Block would recoil from the proposition that the young are the slaves of their maternal parents. But his own reasoning lends force to such an anti-libertarian contention.

The fundamental question in the abortion debate is whether a created person has, by his creation in a state of dependency, a right against his creator to be preserved and protected until the creator can transfer that duty by contract or waiver to another protector or to the created person himself. Rothbard begs this question by holding it “absurd to blame the mother for a birth control mistake … with a birth control mistake, the fetus is the invader”. Of course, if the unborn individual is an “invader”, in the sense of an aggressor, he can have no rightful claim against his mother, by hypothesis. But how an individual can aggressively create himself in a state of dependency on his mother, Rothbard does not explain. If, however, the unborn is himself innocent of aggression, then whether his creation was the result of the mother’s will or a mistake is irrelevant. Legal responsibility for the welfare of others can arise from negligent, as well as from purposeful, acts.

Block, at least, seems to sense that he, Machan, and Rothbard present an insubstantial case for abortion. He admits, for instance, that “[i]f and when medical science defines a method of abortion which does not kill the fetus … then it would be murder to abort in any other way.” But one such non-homicidal method is available today: normal birth. Why the unborn individual would have a right to Block’s special medical procedure but not to the normal birth (followed in both cases, assumedly, by adoption if the mother did not want the child), Block does not say.

Block then attempts to rationalize abortion as a “classical ‘lifeboat’ situation”. He correctly notes that “[t]he cases which fit the lifeboat model are those in which mother and fetus cannot both survive.” But he fails to relate these extraordinary cases to the normal pregnancy in which both individuals do survive.

Finally, Block raises the “Karen Anne Quinlan analogy”. “Suppose’, he muses, “a Karen Anne Quinlan suddenly materializes in someone’s living room comatose and helpless…. [W]hat should the host do?… If other people are willing to accept responsibility for the victim, the host may notify them…. He is not required to keep her alive, but he may not kill her”. What has this to do with abortion? The actual Karen Anne Quinlan case involved a person whose illness was incurable at the prevailing state of the medical arts, but who could be prevented from dying by technological intervention. The Quinlan parents wanted not to intervene in the course of nature when intervention seemed hopeless and unreasonable. The proponents of abortion take a position diametrically opposed to this. They want to intervene in a natural process that normally leads to continued life; whereas the Quinlans wanted to stop intervening in a natural processes that they believed would lead to death. Moreover, in the normal pregnancy situation, the unborn child does not simply “materialize” out of nowhere, but is created by the acts of his father and mother. In addition, at the present level of medical science, not killing the unborn in most cases requires that the mother keep him alive through the natural gestation process. Thus, Block’s reference to the Quinlan case provides arguments against, rather than for, abortion.

In Conclusion

In sum, Block, Machan, and Rothbard fail to establish the legitimacy of abortion. Abortion involves at least four issues: (1) Are there such things as “rights”? (2) Should individuals be forcibly restrained from, and penalized for, violating each other’s “rights”? (3) Do unborn individuals enjoy the same “rights” as those who have been born? (4) What is the content of their “rights”, as against their parents? As far as I am concerned, neither Block, nor Machan, nor Rothbard has answered any of these questions satisfactorily.


All statements quoted here are drawn from Walter Block, Defending the Undefendable (1976); idem, “Woman and Fetus: Rights in Conflict?”, Reason (April 1978; “Toward a Libertarian Theory of Abortion”, Libertarian Forum (September 1977); Tibor Machan, “The Morality of Noninterference”, Reason (April 1978; Murray Rothbard, For a New Liberty, p. 120-121 (1973); idem, “Should Abortion Be A Crime?”, Libertarian Forum, (July 1977).
Dr. Vieira is an attorney practicing constitutional law.

Dr. Edwin Vieria, Jr