Thomoson uses the premise that a fetus is considered a human life from the moment of conception. Though she does not necessarily agree with that statement, she uses it for the sake of the argument. So since the fetus is person, and every person has a right to life, therefore the fetus has a right to life. Although, a woman has the right to determine what happens in and to her body, but the fetus’s right to life is more important than her own. The fetus’s right to life outweighs the mothers right to decide what happens in and to her body. Therefore an abortion may not be performed. This is implying that all abortion is morally impermissible. Thomson proves this through premises that state as to whether or not an abortion can be morally permissible. These premises can be accepted for her argument to be valid. An abortion may be performed in the case of a woman being raped and having a fetus at conception, which makes it morally permissible. There was no consent for the mother to the fetus, and no consent for the mother to have sex with a man in order for conception to happen. Therefore the argument that abortion is morally permissible due to rape is valid.
Thomson then puts the proposed argument for abortion in aspect of an “Extremist View.” The Extremist view is as follows: directly killing of an innocent person (the fetus) is absolutely impermissible. Directly killing an innocent person is murder, and murder is always impermissible. Therefore, killing the fetus is morally impermissible.