The child on the other hand won't be crushed to death; if nothing is done to stop him from growing he'll be hurt, but in the end he'll simply burst open the house and walk out a free man.Thomson concedes that a third party indeed cannot make the choice to kill either the person being crushed or the child.Thomson presents the hypothetical example of the 'expanding child': Suppose you find yourself trapped in a tiny house with a growing child.
"[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 legitimate right to life, but merely deprives the fetus of something—the non-consensual use of the pregnant woman's body and life-support functions—to which it has no right.
Thus, by choosing to terminate her pregnancy, Thomson concludes that a pregnant woman does not normally violate the fetus's right to life, but merely withdraws its use of her own body, which usually causes the fetus to die.
In such a case, the mother's life is being threatened, and the fetus is the one who threatens it.
Because for no reason should the mother's life be threatened, and also for no reason is the fetus threatening it, both are innocent, and thus no third party can intervene.
She gives as an example a hypothetical woman who seeks a late-term abortion "just to avoid the nuisance of postponing a trip abroad" and declares this to be "positively indecent".
Thomson also explicitly rejects the claim that pregnant women have a right to kill their offspring.You don't want children, so you fix up your windows with fine mesh screens, the very best you can buy.As can happen, however, and on very, very rare occasions does happen, one of the screens is defective; and a seed drifts in and takes root.But, Thomson says, the person threatened can intervene, by which justification a mother can rightfully abort.For what we have to keep in mind is that the mother and the unborn child are not like two tenants in a small house, which has, by unfortunate mistake, been rented to both: the mother owns the house.If we say that no one may help the mother obtain an abortion, we fail to acknowledge the mother's right over her body (or property).Thomson says that we are not personally obligated to help the mother but this does not rule out the possibility that someone else may act.Here, the people-seeds flying through the window represent conception, despite the precautionary mesh screen, which functions as contraception.The woman does not want a people-seed to root itself in her house, and so she even takes the measure to protect herself with the best mesh screens, and then voluntarily opens the windows.However, this does not mean that the person being crushed cannot act in self-defense and attack the child to save his or her own life.To liken this to pregnancy, the mother can be thought to be the house, the fetus the growing-child.