The Bystander at the Switch case is a key part of Thomson's argument in "Trolley Problem". The basis of his article is to explain the moral difference between this case, which he deems morally permissible (1398), and the Transplant case, which he deems morally inadmissible (1396). In the Bystander at the Switch case, a passerby sees a cart hurtling toward five workers on the track and has the ability to flip a switch to divert the cart's path toward a single worker. Thomson believes that the Bystander at the Switch case is permissible under two conditions: 1) first, that the same threat is diverted from a larger group to a smaller group of people, and 2) second, that the medium by which this threat is deflected is not in itself a violation of anyone's rights (1407). However, for his thesis to be correct, the Bystander at the Switch case must always be morally permissible. There should be no situation in which it is morally impermissible to kill one and save five. If there were such a situation, in which both parts of Thomson's thesis remained true but it would still be morally impermissible to kill one of them due to some external factor, then Thomson's thesis would no longer be the complete answer. Consider the Mother-Son case. The trolley is still hurtling towards five workers. Here the spectator is a woman who has the ability to flip a switch to divert the cart's path towards a single person. In this case, however, that person is his son. Is it still morally permissible for her to flip the switch? I would have to say no. However, in this case, the decision to flip the switch to divert the trolley's path still satisfies both of Thomson's conditions... mid-paper... might be able to understand why the mayor would break his promise and he would flip the switch, but he would never accept why the mother would flip the switch and kill her son. The mother-son case illustrates that there are more factors at play than just the two Thomson presents in his thesis. Thomson's condition alone cannot explain every situation. The relationship between the people involved can also influence whether or not a decision is moral. If such a relationship implies that one person is emotionally bound and ethically responsible for the safety and well-being of the other, the former cannot knowingly contribute to the death of the latter. Thomson's thesis must be modified to include this condition as well. Works Cited Thomson, Judith J. “The Trolley Problem.” The Yale Law Journal 94.6 (1985): 1395-415. JSTOR. Network. January 20. 2009.