A Defense of Abortion

A Defense of Abortion is a moral philosophical paper by Judith Jarvis Thomson first published in 1971. Granting for the sake of argument that the fetus has a right to life, Thomson uses thought experiments to argue for the moral permissibility of induced abortion. Her argument has many critics on both sides of the abortion debate, yet continues to receive defense. Thomson's imaginative examples and controversial conclusions have made A Defense of Abortion perhaps "the most widely reprinted essay in all of contemporary philosophy".

Overview of the essay
In A Defense of Abortion, Thomson grants for the sake of argument that the fetus has a right to life, but defends the permissibility of abortion by appeal to a thought experiment:
 * You wake up in the morning and find yourself back to back in bed with an unconscious violinist. A famous unconscious violinist. He has been found to have a fatal kidney ailment, and the Society of Music Lovers has canvassed all the available medical records and found that you alone have the right blood type to help. They have therefore kidnapped you, and last night the violinist's circulatory system was plugged into yours, so that your kidneys can be used to extract poisons from his blood as well as your own. [If he is unplugged from you now, he will die; but in nine months] he will have recovered from his ailment, and can safely be unplugged from you.

Thomson takes it that you may now permissibly unplug yourself from the violinist even though this will cause his death: the right to life, Thomson says, does not entail the right to use another person's body, and so by unplugging the violinist you do not violate his right to life but merely deprive him of something&mdash;the use of your body&mdash;to which he has no right. "[I]f you do allow him to go on using your kidneys, this is a kindness on your part, and not something he can claim from you as his due."

For the same reason, Thomson says, abortion does not violate the fetus's right to life but merely deprives the fetus of something&mdash;the use of the pregnant woman's body&mdash;to which it has no right. Thus, it is not that by terminating her pregnancy a woman violates her moral obligations, but rather that a woman who carries the fetus to term is a 'Good Samaritan' who goes beyond her obligations.

Criticism
Critics of Thomson's argument (see the table below) generally grant the permissibility of unplugging the violinist, but attempt to block the inference that abortion is permissible by identifying morally relevant disanalogies between the violinist scenario and typical cases of abortion. The most common objection is that Thomson's argument can justify abortion only in cases of rape. In the violinist scenario, you were kidnapped: you did nothing to cause the violinist to be plugged in, just as a woman who is pregnant due to rape did nothing to cause her pregnancy. But in typical cases of abortion, the pregnant woman had intercourse voluntarily, and thus (it is said) has either tacitly consented to allowing the fetus to use her body (the tacit consent objection), or else has a duty to sustain the fetus because the woman herself caused the fetus to stand in need of her body (the responsibility objection). Other common objections turn on the claim that the fetus is the pregnant woman's child whereas the violinist is a stranger (the stranger versus offspring objection), or that abortion kills the fetus whereas unplugging the violinist merely lets him die (the killing versus letting die objection).

Defenders of Thomson's argument reply that the alleged disanalogies between the violinist scenario and typical cases of abortion do not hold, either because the factors that critics appeal to are not genuinely morally relevant, or because those factors are morally relevant but do not apply to abortion in the way that critics have claimed. A summary of common objections and responses is below.

Less common objections to Thomson's argument include:
 * the natural-artificial objection : pregnancy is a natural process that is biologically normal to the human species. The joined condition of the violinist and donor, in contrast, represents an extreme and unusual form of "life support" that can only proceed in the presence of surgical intervention.  This difference is morally relevant and therefore the two situations should not be used to model each other;
 * the conjoined twins objection : the relationship between conjoined twins represents a more complete analogy to pregnancy than the relationship between the violinist and the kidney donor. Because the fatal separation of conjoined twins is immoral, so is abortion;
 * the different burdens objection : supporting the violinist is a much greater burden than normal pregnancy, and so unplugging the violinist is morally permissible whereas aborting the fetus is not;
 * the artificiality objection : our intuitions on bizarre thought experiments of the sort used by Thomson are unreliable and provide no warrant for the conclusions they are intended to support; and
 * the duty to sustain the violinist objection : despite the common intuition, one does have an obligation to support the violinist, and likewise the fetus.

Defenders of Thomson's argument have responses to these less common objections as well. For example, the analogy between typical pregnancy and conjoined twins has been challenged on the basis that the pregnant woman, having existed for many years before the fetus came into existence, has a prior claim to the use of her own body, whereas conjoined twins come into existence at the same time and thus do not have a prior claim to the use of their shared body parts. Of course, critics have replies to these responses, and so the debate goes back and forth.