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The claims to which partisans on both sides of the "abortion" issue appeal seem, if one is not thinking of the abortion issue, close to self-evident, or they appear to be easily defensible. The case against abortion (Beckwith 1993) rests on the proposition that there is a very strong presumption that ending another human life is seriously wrong. Almost everyone who is not thinking about the abortion issue would agree. There are good arguments for the view that fetuses are both living and human. ("Fetus" is generally used in the philosophical literature on abortion to refer to a human organism from the time of conception to the time of birth.) Thus, it is easy for those opposed to abortion to think that only the morally depraved or the seriously confused could disagree with them.

Standard pro-choice views appeal either to the proposition that women have the right to make decisions concerning their own bodies or to the proposition that fetuses are not yet persons. Both of these propositions seem either to be platitudes or to be straightforwardly defensible. Thus, it is easy for pro-choicers to believe that only religious fanatics or dogmatic conservatives could disagree. This explains, at least in part, why the abortion issue has created so much controversy. The philosophical debate regarding abortion has been concerned largely with subjecting these apparently obvious claims to the analytical scrutiny philosophers ought to give to them.

Consider first the standard argument against abortion. One frequent objection to the claim that fetuses are both human and alive is that we do not know when life begins. The reply to this objection is that fetuses both grow and metabolize and whatever grows and metabolizes is alive. Some argue that the beginning of life should be defined in terms of the appearance of brain function, because death is now defined in terms of the absence of brain function (Brody 1975). This would permit abortion within at least eight weeks after conception. However, because death is, strictly speaking, defined in terms of the irreversible loss of brain function, the mere absence of brain function is not a sufficient condition for the absence of life. Accordingly, the claim that the presence of brain function is a necessary condition for the presence of life is left unsupported. Also, the standard antiabortion argument is criticized on the ground that we do not know when the soul enters the body. However, such a criticism is plainly irrelevant to the standard, apparently secular, antiabortion argument we are considering.

The Thomistic premise that it is always wrong intentionally to end an innocent human life is used by the Vatican to generate the prohibition of abortion. This premise is often attacked for presupposing "absolutism." This Vatican principle seems to render immoral active euthanasia, even when a patient is in excruciating, unrelievable pain or in persistent coma; it even seems to render immoral ending the life of a human cancer-cell culture. In none of these cases is the individual whose life is ended victimized. Thus, the Vatican principle seems most implausible.

Opponents of abortion are better off appealing to the weaker proposition that there is a very strong presumption against ending a human life (Beckwith 1993). Because this presumption can be overridden when the victim has no interest in continued life, use of this premise provides a way of dealing with the above counterexamples. However, this tactic provides room for another objection to the antiabortion argument. Some pro-choicers have argued that insentient fetuses have no interest in continued life. Because what is insentient does not care about what is done to it and because what does not care about what is done to it cannot have interests, insentient fetuses cannot have an interest in living. Therefore, abortion of insentient fetuses is not wrong (Steinbock 1992, Sumner 1981, and Warren 1987).

If this argument were sound, then it would also show that patients who are in temporary coma, and therefore insentient, do not have an interest in living. M. A. Warren (1987) attempts to avoid this counterexample by making the neurological capacity for sentience a necessary condition for having any interests at all and, therefore, for having an interest in living. This move does not solve the problem, however. Because the argument in favor of permitting the abortion of insentient fetuses generated an untenable conclusion, that argument must be rejected. Because the argument rests on an equivocation between what one takes an interest in and what is in one's interest, there are even better reasons for rejecting it. Accordingly, this objection to the standard antiabortion argument is unsupported.

The classic antiabortion argument is subject to a major theoretical difficulty. Antiabortionists have tried vigorously to avoid the charge that they are trying to force their religious views upon persons who do not share them. However, the moral rule to which the standard antiabortion argument appeals obtains its particular force in the abortion dispute because it singles out members of the species Homo sapiens (rather than persons or sentient beings or beings with a future like ours, for example). It is difficult to imagine how the Homo sapiens rule could be defended against its competitors without relying upon the standard theological exegesis of the Sixth Commandment and upon the divine-command theory on which its moral standing rests. This leads to two problems. First, arguments against divine-command ethical theory seem compelling. Second, when arguments based on divine-command theory are transported into the Constitutional realm, First Amendment problems arise.

The philosophical literature contains two major kinds of pro-choice strategies. The personhood strategy appeals to the proposition that no fetuses are persons. If this is so, then, because a woman plainly has the right to control her own body if she does not directly harm another person, abortion is morally permissible. However, Judith Thomson (1971) has argued that a woman's right to control her own body can justify the right to an abortion in some situations even if fetuses are persons. This second strategy rests on the claim that no one's right to life entails the right to a life-support system provided by another's body even if use of that life-support system is the only way to save one's life. Thus, even if opponents of abortion are successful in establishing that fetuses have the right to life, they have not thereby established that any fetus has the right to anyone else's uterus.

It is widely believed that Thomson's strategy can justify abortion in cases of rape and in cases where the life of a pregnant woman is threatened by pregnancy (Warren 1973). There is much less unanimity concerning other cases, because it is generally believed that, if we create a predicament for others, we have special obligations to help them in their predicament. Furthermore, let us grant that A's right to life does not entail A's right to B's body even when A needs B's body to sustain life. Presumably, by parity of reasoning, B's right to B's body does not entail B's right to take A's life even if A's continuing to live severely restricts B's choices. Thus, we have a standoff, and the winner from the moral point of view will be that individual with the strongest right. Although Thomson's strategy has been widely discussed and raises interesting questions about the duty of beneficence, questions both about its philosophical underpinnings and about its scope suggest that philosophically inclined pro-choicers would be better off with a personhood strategy.

No doubt, this is why personhood strategies have dominated the pro-choice philosophical literature. Such strategies come in many varieties (Engelhardt 1986; Feinberg 1986; Tooley 1972, 1983, and 1994; and Warren 1973, 1987). Warren's 1973 version is most famous. She argued that reflection on our concept of person suggests that in order to be a person one must possess at least more than one of the following five characteristics: consciousness, rationality, self-motivated activity, the capacity to communicate, and the presence of a concept of self. Since no fetus possesses any of these characteristics, no fetus is a person. If only persons have full moral rights, then fetuses lack the full right to life. Therefore, abortion may never be forbidden for the sake of a fetus.

One might object to such a strategy on the ground that, since fetuses are potential persons, the moral importance of personhood guarantees them a full place in the moral community. The best reply to such an objection is that the claim that X 's have a right to Y does not entail that potential X 's have a right to Y (think of potential voters and potential presidents; Feinberg 1986).

Although personhood theorists (like antiabortionists) tend to say little about the moral theories on which their views rest (Engelhardt 1986 is an interesting exception), presumably most personhood theorists will turn out to be, when driven to the wall, social-contract theorists. Such theories, according to which morality is a self-interested agreement concerning rules of conduct among rational agents, tend to have problems accounting for the moral standing of those who are not rational agentsbeings such as animals, young children, the retarded, the psychotic, and the senile. Thus, the personhood defense of the pro-choice position tends to have problems that are the inverse of those of the classic antiabortion argument.

Both standard antiabortion and personhood accounts appeal, in the final analysis, to the characteristics fetuses manifest at the time they are fetuses as a basis for their arguments concerning the ethics of abortion. This appeal may be a mistake both defenses share. My premature death would be a great misfortune to me because it would deprive me of a future of value. This is both generalizable and arguably the basis for the presumptive wrongness of ending human life. Such a view seems to imply that abortion is seriously immoral, seems to have a defensible intuitive basis, and seems to avoid the counterexamples that threaten alternative views (Marquis 1989). However, this view is subject to two major objections. One could argue that the difference between the relation of fetuses to their futures and the relation of adults to their futures would explain why adults are wronged by losing their futures but fetuses are not (McInerney 1990). One might also argue that because human sperm and ova have valuable futures like ours, the valuable future criterion for the wrongness of killing is too broad (Norcross 1990). Not everyone believes these objections are conclusive.

See also Animal Rights and Welfare; Bioethics; Rights.


Beckwith, Francis J. Politically Correct Death: Answering Arguments for Abortion Rights. Grand Rapids, MI: Baker, 1993.

Boonin, David. A Defense of Abortion. Cambridge, U.K.: Cambridge University Press, 2003.

Brody, Baruch. Abortion and the Sanctity of Human Life: A Philosophical View. Cambridge, MA: MIT Press, 1975.

Burgess, J. A., and S. A. Tawia. "When Did You First Begin to Feel It? Locating the Beginning of Human Consciousness." Bioethics 10 (1) (1996): 126. An extremely useful discussion for sentience-based views.

Davis, Nancy. "Abortion and Self-Defense." In Abortion: Moral and Legal Perspectives, edited by Jay L. Garfield and Patricia Hennessey, pp. 186210. Amherst: The University of Massachusetts Press, 1984.

Dworkin, Ronald. Life's Dominion: An Argument about Abortion, Euthanasia, and Individual Freedom. New York: Knopf, 1993.

Engelhardt, H. Tristam, Jr. The Foundations of Bioethics. New York: Oxford University Press, 1986. An attempt to place the personhood strategy in the context of an ethical theory and other issues in bioethics.

English, Jane. "Abortion and the Concept of a Person" (1975). In Arguing about Abortion, edited by Lewis M. Schwartz, pp. 159198. Belmont, CA: Wadsworth, 1993.

Feinberg, J. "Abortion." In Matters of Life and Death: New Introductory Essays in Moral Philosophy. 2nd ed., edited by Tom Regan. New York: Random House, 1986. The best account of the personhood strategy in a single essay.

Ford, Norman M. When Did I begin? Conception of the Human Individual in History, Philosophy and Science. Cambridge, U.K.: Cambridge University Press, 1988. An excellent discussion of issues relevant to the moral status of the early embryo.

Hare, R. M. "Abortion and the Golden Rule" (1975). In his Essays on Bioethics, pp. 147167. Oxford: Clarendon, 1993.

Hare, R. M. "A Kantian Approach to Abortion" (revised version, 1989). In his Essays on Bioethics, pp. 168184. Oxford: Clarendon, 1993.

Hursthouse, Rosalind. "Virtue Theory and Abortion." Philosophy and Public Affairs 20 (3) (Summer 1991): 223246.

Kamm, F. M. Creation and Abortion: A Study in Moral and Legal Philosophy. New York: Oxford University Press, 1992. A defense of Thomson's strategy.

Lee, Patrick. Abortion and Unborn Human Life. Washington, DC: The Catholic University of America Press, 1996. One of the best book-length cases against abortion.

Marquis, Donald. "Why Abortion Is Immoral." Journal of Philosophy 86 (1989): 183202.

McInerney, Peter. "Does a Fetus Already Have a Future-Like-Ours?" Journal of Philosophy 87 (1990): 265268.

McDonagh, Eileen L. Breaking the Abortion Deadlock: From Choice to Consent. Oxford: Oxford University Press, 1996. Defends a self-defense variant of Thomson's strategy.

Norcross, A. "Killing, Abortion, and Contraception: A Reply to Marquis." Journal of Philosophy 87 (1990): 268277.

Pojman, Louis J., and Francis J. Beckwith, eds. The Abortion Controversy: 25 Years after Roe v. Wade: A Reader. 2nd ed. Belmont, CA: Wadsworth, 1998. An excellent anthology.

Quinn, Warren. "Abortion: Identity and Loss." In his Morality and Action, pp. 2051. Cambridge, U.K.: Cambridge University Press, 1993.

Schwarz, Stephen. The Moral Question of Abortion. Chicago: Loyola University Press, 1990. A useful book-length argument against abortion.

Steinbock, Bonnie. Life before Birth: The Moral and Legal Status of Embryos and Fetuses. New York: Oxford University Press, 1992. A sentience strategy.

Stone, Jim. "Why Potentiality Matters." Canadian Journal of Philosophy 17 (4) (December 1987): 815830.

Sumner, L. W. Abortion and Moral Theory. Princeton, NJ: Princeton University Press, 1981. A sentience strategy.

Thomson, Judith Jarvis. "A Defense of Abortion." Philosophy and Public Affairs 1 (1971): 4766. A classic paper.

Tooley, M. "Abortion and Infanticide." Philosophy and Public Affairs 2 (1972): 3765. A classic paper.

Tooley, M. Abortion and Infanticide. New York: Oxford University Press, 1983.

Tooley, M. "In Defense of Abortion and Infanticide." In The Abortion Controversy: A Reader, edited by L. P. Poman and F. J. Beckwith. Boston: Jones and Bartlett, 1994.

Warren, Mary Anne. "The Abortion Issue." In Health Care Ethics: An Introduction, edited by D. VanDeVeer and T. Regan. Philadelphia: Temple University Press, 1987. A sentience strategy combined with a personhood strategy.

Warren, Mary Anne. "On the Moral and Legal Status of Abortion." Monist 57 (1973): 4361. A classic paper.

Don Marquis (1996)

Bibliography updated by David Boonin (2005)

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