Judith Jarvis Thomson argued that if you connect a man who needs to be connected to a woman to stay alive for nine months that she clearly has the right to disconnect him though it will kill him.  It is her body.  From this it appears the mother has the right to abort her unwanted unborn child.  It is clear that body autonomy comes before even the right to life of another.
Let us look at the objections to Thomson's reasoning.
First the Tacit Consent Objection.  The woman has sex to get pregnant. She tacitly consented to get pregnant so she will not have the right to have an abortion
The objections to this are as follows:
* Tacit consent cannot be inferred where contraception was used or when the woman thought she was safe.
* What if the woman had been drunk?
* Engaging in a voluntary action while foreseeing a certain result does not entail that one has tacitly consented to that result.
* The woman then it seems just because it is her job to look after the child seems to be bound to do so when it is in the room and after it is born. She must do this because she tacitly consented to the conception. What about the man? The woman has the right to refuse to let a father see his child. But this Tacit Consent theory implies that by having sex the man gives his life to look after the child forever. The argument is purely sexist for it ignores the man and seeks to impose a duty on the woman.
* Even if the woman has tacitly consented to the fetus making demands on her body, it does not follow that she has consented to sustain it for the entire nine months of pregnancy. Why should tacit consent be final? People are allowed to change their minds. People promise to get married when they are engaged and things change and they can break the engagement without feeling bound to the promise. Nobody says, "You vow yourself to a person for life when you are engaged and to break the engagement is wrong unless you discover your partner was never genuine".
* The consent argument would only help a person who believed in free will. Some people don’t and many hold that its role is not significant enough. Some believers in free will hold that the free will belief cannot be forced on anybody and should not be. They would have to hold that abortion should be permitted legally to allow people to make their own decisions.
* Consent is not more important than a person’s right to their own body. If you consent to give a kidney to your friend you can change your mind even if they will die after. 
Second, the responsibility objection. The pregnant woman voluntarily engaged in sexual intercourse with the result that the fetus stands in need of the use of her body to survive. The woman is thus responsible for the fetus's need to use her body and so the fetus has a right to use her body. No such responsibility occurs with the violinist (or pregnancy due to rape).
The objection to this is as follows:
* The woman is responsible for the fetus existing, but as she could not have caused the fetus to exist without it being dependent on her, she is in a relevant sense not responsible for the fetus's need to use her body. She didn’t make the rule that babies in the womb need the mother’s body.
Thomson raises the responsibility objection herself and concludes it is not convincing.
First, she offers an argument that lends support to the view that abortion is justified at least in the case of rape, the argument that we have seen that involves the violinist scenario.
Second, she points out that one cannot drive a wedge between rape and other cases simply by appealing to the fact that in other cases the woman is responsible for there being a fetus that needs assistance, since the woman is also to some extent responsible in cases of rape (e.g., she could get a hysterectomy).
Therefore Thomson concludes that abortion is morally permissible in at least some cases where intercourse is voluntary.
* When you get married you take on the responsibility for somebody else’s happiness for life. But separation and divorce are allowed and indeed should be so it does not follow that just because a woman had sex and got pregnant that she is responsible for the pregnancy and so should keep the baby.
* Somebody else’s body is not more important than a person’s right to their own body. If you consent to give a kidney to your friend you can change your mind even if they will die after.
* If a woman is responsible for her baby and that means she cannot have an abortion then it must also mean that she is bound to keep the baby and discount adoption as an option. The responsibility argument would mean that adoption is wrong.
Third, Stranger versus offspring objection. Parents have special obligations towards their offspring (as shown, for example, by laws requiring child support payments and by the fact that child abandonment is morally wrong). The fetus is the pregnant woman's offspring, and so she has a special obligation to sustain it; the violinist is a stranger and so you have no such obligation.
The objections to this are as follows:
* Special obligations do not arise from mere biological relatedness; they can only be assumed, either explicitly or implicitly. For example, by taking the baby home from the hospital one implicitly agrees to care for it. But one still has the right to put ones child up for adoption after.
* Even special parental obligations do not require parents to undergo organ donation or other direct use of their body (such as pregnancy) for the sake of their offspring. A mother does not have to give a kidney she can spare to save her child even if there is no other way to save him.
* From the fact that it is morally permissible for a society to enact child support laws, it does not follow that there is any obligation (to the child) to pay child support independently of such laws. Laws are really only human constructs. If we lived in a world where teddy bears looked after abandoned babies there would be no laws and no obligation to give money to one’s child.
* The wrongness of child abandonment may suggest we have some positive duties towards others; but it would not follow that those duties are strong enough to require sustaining the fetus.
* What do you say to the person who believes people should be valued because they are people not because they are relations or friends? Jesus said that anybody who loved those who loved them had done nothing to be rewarded for. If you value your mother because she is your mother, that means if she was another person you wouldn’t value her the same. So she is not valued because of who she is but because of what she is. Some would argue "Letting a person like the violinist die because they owe you nothing is evil. It implies that what matters is not the person but what they owe you." But this is not like a woman having her baby aborted for the baby is in her body and is not wanted there. The issue is that the body is the woman’s. The woman is not degrading the child but asserting her right over her body.
* If abortion is wrong, letting the violinist die is also wrong. The view that you can hurt a stranger but not your baby doesn’t hold water. If a baby deserves your devotion for it is related to you, how much more does a kindly adult who isn’t related to you. Suppose the concept of deserving is correct. Strangers have respected us at least after the manner of doing us no harm. Strangers might save your life if you were lying dying. A person should be rewarded for what they would do as well as what they do do. You can't condemn anybody for trying even if they get no further than wishing. I would add that people should be rewarded for what they are and being a person means you always have the right to be respected. You deserve to be respected just because you are a person even if you never did a good deed in your life. The concept of deserving according to your good or bad deeds is a dangerous one for it suggests that you should pay for hating by being hated. Thomson is wrong to suggest that we owe strangers no salvation if they are hurt or dying. This tells us that the violinist IS in the same position as a fetus. If you can abort one you can abort the other! If you can let one die you can let the other die.
Fourth, Killing versus letting die objection. There is a morally relevant difference between killing and letting die. Abortion typically kills the fetus and thus is impermissible, but unplugging the violinist merely lets him die and so is permissible. The objection would not apply to 'merely extractive' methods of abortion (such as hysterotomy) where the fetus is extracted intact and then allowed to die rather than killed.
The objections to this are as follows:
* So letting some lunatic blow people up is not as bad as doing it yourself? There will still be people dead at the end of it.
* Pro-lifers do not hold that merely extractive abortions are less objectionable than other methods of abortion; so they cannot consistently raise the killing versus letting die objection.
* Even if killing is substantially worse than letting die, it is justified in the case of abortion because letting die would require a merely extractive abortion, which under current technology involves substantial risk to the pregnant woman.
* Killing is not in and of itself worse than letting die, or is not sufficiently worse to undermine the violinist analogy. You can let a person die and cause a lot more trouble than you would cause if you went and killed someone. And besides you are still intending for somebody to die in either case. Unplugging somebody’s life support (except when they are brain dead) is as much trying to kill them as stabbing them in the heart is. Letting a person die can make the person suffer terribly as they die when smothered them would be kinder. Letting a person die can make it all go wrong. Perhaps you will leave the victim brain-damaged and the person will not die after all.
* You are guilty of murder in the legal sense when you deliberately kill somebody. If you did not mean to do it, it is not murder. If you did mean to but failed as far as you as a person are concerned you are a murderer in your intent and in your heart. Letting a person die is as much murder as is shooting them to death when the intention to cause death is there - if you are too lazy to help your intention is: "I want that person to lose her life for I can't be bothered helping". You are harming them by neglect for they would live otherwise and you neglect them because you want to kill if you think it will kill them. You can't say that it was not murder if you gave your father a mild poison to kill him though there was a chance it would not kill him at all. You can't justly neglect a stranger because he never got the chance to help you.
* The morality really says that the sin of killing a person is not the same as letting die which is permitted at times. This really says that morality is about rules irrespective of consequences. It is rule that matter not preventing harm. It is okay to let somebody die when that would be a worse evil than killing them outright. It is all right to leave a man cut in half on a battlefield to die rather than for you to decapitate him to put him out of his misery. If consequences don’t matter then executing a person for breaking the Sabbath could conceivably be permissible.
Fifth, Intending versus foreseeing objection, There is a morally relevant difference between intending harm and causing harm as a foreseen but unintended side-effect.

Example, John steals from rich Amy because it is the only way he can feed sick Charlie. The harm done to Amy is an unintended side-effect. He is not doing it to hurt her but to help Charlie. If it were not the only way, clearly John would have been intending to hurt Amy. If refraining from stealing is more important than helping the sick then clearly John would have been intending to hurt Amy.
It follows then that alcoholics should not be penalised for stealing drink because it is not done to steal but to cope with an overwhelming need for drink.
You may hear, "In most cases, abortion intentionally causes the fetus's death and so is impermissible; whereas unplugging the violinist causes death as an unintended side-effect and so is permissible."
So it is about your intention not how you are causing a death.  This contradicts every single code of morality in existence.

Some who agree with much of the argument would say, “Thomson is right that you have the right to refuse if somebody needs to be connected to your body by some kind of machine to keep them alive which will mean you will not be able to move from a bed for months. For the same reason, a mother has the right to have an abortion. However, the earlier the abortion the better. It is clear that a woman having an abortion four months before the birth could have waited for four months is not that long and would be doing wrong for the life of the child is more important than four months inconvenience.”
Here are the objections:
* You can survive being plugged up to somebody for nine months. But as a result of your decision to unplug yourself the violinist will die. He will not survive. Yet believers in the argument approve if you unplug yourself and inconsistently insist that you shouldn’t have an abortion if you don’t want to be pregnant.
* The issue is the right to make your own decisions for your own body. Even if the baby has a right to life it doesn’t follow that the mother must be compelled to continue with the pregnancy. She may have the right to have an abortion.
* Suppose I am a woman. I am surer that I exist than that anything outside of me exists. I am aware therefore I am. I cannot doubt that I am conscious. Therefore my right to control my body comes first. If I get pregnant I have the right to an abortion when I don’t want to be pregnant. I am less sure that the baby inside me is a person than that I am or that any born child is. The nearer to conception I go the less sure I am that the baby is a person or a person with rights equal to mine.
* If persons are as valuable as that then it follows that it is better to be tormented to the extreme forever and ever than to die peacefully. Those who preach the argument don’t go that far so they don’t really believe in it.
* They say that dying people should be given pain killers that make them die faster. They say the purpose is to make the patients more comfortable not to kill them. But this is hypocrisy. You would be forgiven for thinking the following. Some doctors will give the painkillers in the hope of killing the patients to put them out of their misery and make more room in the hospital for new patients. And others will do it to kill the pain. Some will do it for both. It is as silly as saying that a woman hitting her child in a temper did so to exercise her hand or to test that the child reacted normally to pain. If life is more important than suffering then it is wrong to give the painkillers when they will draw an impending death far closer. It is helping death along. It is contributing to the person’s death. If that is not murder then it is not murder to put the bullets in a gun for your friend to shoot your enemy with. Then it is not murder if a group of boys beat a pensioner to death if you were in the group and didn’t deliver any blows that were as deadly as those of the others. You would still be classed as a murderer for that.
Seventh, the baby is innocent and deserves to live and so abortion is wrong.
* This ignores the fact that Thomson herself says that a baby has a right to life but she says the baby does not have the right to take over its mother’s body so she can have an abortion if she wishes.


* The mother is innocent too but we must remember that pro-life people think that if she would abort whatever the reason she is not and never will be an innocent person again even if she is forgiven by God and everybody else.
* Judith Jarvis Thomson was convinced that abortion is permissible for the child never did anything for the mother and so has no right to any favours from her though she has no right to hurt it gratuitously. She is allowed to have an abortion for it is her body but she is not allowed to torment the child unnecessarily. Thomson argues that though a stranger is not to kill you, that the stranger may let you die for she or he doesn't owe you anything. But she is wrong in this. The baby never got the chance to be good to its mother to deserve anything from her. In that sense, it does deserve. People should be blessed for the good they might have done but never got the chance to do. You have to assume the best of them. If you can’t kill a person when they do you a favour, then what they did for you is more important than their right to life. If you are that important then it is hard to see why you can’t kill them anyway.
* But though the baby might have the right to live it doesn’t follow that it deserves to live. Murderers have the right to live but they don’t deserve to live.
* The innocence of the fetus does not mean that the mother should let it invade her body. The issue is that the woman owns her own body.
Some say that the baby is a part of the mother and so she can do what she pleases with her own body. Anti-abortionists respond that this would still make abortion evil for then it would be mutilation. But it is not mutilation any more than cutting off a lump you deliberately grow on your arm would be. It is not an essential part of the body so its removal does not constitute mutilation.

No argument that the mother who has an unwanted pregnancy consents to the baby being in her womb works.  Thomson however is the thinker who has led many to think that if the woman has not consented as in rape she can abort.  But it would have to be removing the baby for it to die by itself.


The refutations of Thomson’s position fail. The refutations being unsuccessful don’t mean that she is right but make it likely that she is unless new refutations can be thought of.
Nobody has the right to dogmatically oppose her argument.