American philosopher Judith Thomson takes on the debate of abortion by presenting an analogical argument. She uses other several analogical arguments throughout her paper but the most appealing analogical argument is the sick violinist example. To begin Thomson assumes that the fetus has a right to life from the moment of conception (Thomson, CC 37) Imagine that you wake up one morning to find you've attached to a famous unconscious violinist. The violinist is attached to you because he needs your kidneys and you were the only individual to share the same blood type as the violinist (Thomson, CC 37). The doctor tells you that to keep the violinist alive he needs to be attached to you for nine months or even more and unplugging yourself would mean killing him immediately (Thomson, CC 37). Furthermore, the doctor explains that all persons have a right to life and violinist is a person, so the violinist has a right to life, but because a person's right to life is more important than your own individual right you cannot unplug yourself, therefore in doing so would be morally impermissible. (Thomson, CC 37) .
So how does Thomson use this example to justify abortion? She simply uses the sick violinist example to build an analogical argument to further strengthen her position. Even if we assume that the fetus is a person abortion is not a violation to the fetus right to life and therefore considered as unjustified killing. The mother or the person (in the violinist example) has no moral obligation to save the person/fetus. A person in this case is something with the right to life and therefore applies to the both the violinist example and fetus. On the other hand murder is unjust morally wrong killing, in some cases in self-defense. Therefore in Thomson's violinist example unplugging yourself from the violinist would not be considered as murder. Murder isn't just killing the other person it is morally unjustified killing.