The most famous illustration in Thomson's paper is that of the sickly violinist. You awaken one morning to find that you have been kidnapped and this violinist has been attached to your kidneys. The violinist has a condition with which he is unable to live on his own, and a society of music lovers has attached him to you, knowing that you alone have the only blood type capable of keeping him alive. Now awake and aware of your situation, you face a moral dilemma. Since as a member of the human race the violinist has a right to life, you would seem to be unable to unplug him without violating this right and killing him. However, if you leave the violinist attached to you, you face months unable to move, though you in no way gave him the right to use your body in such a way.
Thomson wishes to show that the right to life does not include the right to be given the means necessary for survival. If the right to life entails the right to be given the means for survival, you are unjustified in preventing the violinist from having something imperative to his survival. In this case, that would be the ongoing use of your kidneys. The right to the ongoing use of your kidneys necessarily implies that the violinist's right to the means for survival trumps your right to your body, something which Thomson cannot allow to be. She says that ``the fact that for continued life that violinist needs the continued use of your kidneys does not establish that he has a right to be given the continued use of your kidneys'' (146-147). You have a right to how your body is used, Thomson says, and the violinist has no right that demands you give him its use. Therefore, you are morally justified in not giving him the use of your kidneys.
Similarly, Thomson also wishes to show that the right to life does not include the right not to be killed. If the violinist possesses the right not to be killed, then you are unjustified in removing the plug from your kidneys, though it has already been established that the violinist has no right to their use. Thomson again points out that the violinist has no right to your body, and therefore you cannot be unjust in unplugging him. ``You surely are not being unjust to him, for you gave him no right to use your kidneys, and no one else can have given him any such right'' (147). If you are not unjust in unplugging yourself from him, and he has no right to the use of your body, then your action cannot be wrong, though the result of your action is that the violinist is killed.
These arguments are very convincing in their redefinition of the right to life, but it fails to follow that therefore modern abortion techniques are justified. Thomson establishes that the woman's right to the use of her body is a more stringent right than the right not to be killed, but then her conclusion that this makes abortion permissible seems to ignore the distinctions that must be drawn between the right to not be killed and the right to kill. Modern abortion techniques work not by removing that which the fetus needs for survival, and thereby allowing it to be killed, but by killing and then removing the fetus. For clarification of this distinction, it may be helpful to look again at Thomson's violinist analogy. Thomson argues, and logically so, that you are completely justified in denying the violinist further use of your body and unplugging him from you. She would, however, likely be loath to argue that because the violinist has no right to the use of your body, you are therefore justified in strangling him in the process of removing the plug. In the former case you are presented with taking an action which would most likely lead to the violinist's death, in the latter you have the direct act of killing the violinist. If current techniques are more like the latter, they would seem to be in opposition to even Thomson's narrowed right to life.
A possible response to this argument would be to claim that current abortion techniques are merely exacting the same end as would be reached given a technique that removed the means for survival without directly killing the fetus. In either case, the fetus will end up the same, and current techniques are the most effective way of cleanly bringing about that end. Any minor discrepancies that exist between the established right and the execution of this right are technicalities, solely the result of our imperfect technologies.
This response ignores the basic premise that moral theory is required to trump issues of expedience. If current techniques are acceptible because of their availability and the lack of an alternative which stringently fulfills the requirements of a right to life, then expedience is the determining factor. Therefore either the right to life is being violated, or the right to life is not a moral imperative. Neither of these are conclusions acceptable to Thomson, who feels that ``the primary control we must place on the acceptability of an account of rights is that it should turn out in that account to be a truth that all persons have a right to life'' (147). Thomson intends to show that abortion can exist within a moral code.
Thomson's paper was highly successful in arguing for a redefinition of the abortion debate. Her logical arguments on the entailments of a right to life were highly original and have provoked much further debate. Her skills in reasoning would likely lead her to find a much stronger rebuttal of the issue presented here. As it stands, however, her arguments fail to account for discrepancies between theory and present practice and therefore cannot be accepted to be a full moral justification for abortion.