A rigorous treatment of a thought experiment that has become notorious within and outside of philosophy - The Trolley Problem - by one of the most influential moral philosophers alive today
Suppose you can stop a trolley from killing five people, but only by turning it onto a side track where it will kill one. May you turn the trolley? What if the only way to rescue the five is to topple a bystander in front of the trolley so that his body stops it but he dies? May you use a device to stop the trolley that will kill a bystander as a side effect? The "Trolley Problem" challenges us to explain and justify our different intuitive judgments about these and related cases and has spawned a huge literature. F.M. Kamm's 2013 Tanner Lectures present some of her views on this notorious moral conundrum. After providing a brief history of changing views of what the problem is about and attempts to solve it, she focuses on two prominent issues: Does who turns the trolley and how the harm is shifted affect the moral permissibility of acting? The answers to these questions lead to general proposals about when we may and may not harm some to help others.
Three distinguished philosophers - Judith Jarvis Thomson (one of the originators of the trolley problem), Thomas Hurka, and Shelly Kagan - then comment on Kamm's proposals. She responds to each comment at length, providing an exceptionally rich elaboration and defense of her views. The Trolley Problem Mysteries is an invaluable resource not only to philosophers concerned about the Trolley Problem, but to anyone worried about how we ought to act when we can lessen harm to some by harming others and how we can reach a decision about the question.

F. M. Kamm is Littauer Professor of Philosophy and Public Policy in the Kennedy School of Government at Harvard University. Kamm is a Professor of Philosophy, Faculty of Arts and Sciences within the Philosophy Department at Harvard University. Kamm is also author of Intricate Ethics (OUP 2010) and Bioethical Prescriptions (OUP 2013), and others.
Eric Rakowski is Edward C. Halbach Jr. Professor of Law at University of California Berkeley.

List of Contributors
Introduction
Eric Rakowski
The Trolley Problem Mysteries
F.M. Kamm
Lecture I: Who Turned the Trolley?
Lecture II: How Was the Trolley Turned?
Diagrams
Comments
Kamm on the Trolley Problems
Judith Jarvis Thomson

Trolleys and Permissible Harm
Thomas Hurka

Solving the Trolley Problem
Shelly Kagan

F.M Kamm
Trolley Problem Mysteries on Trial: Defending the Trolley Problem, A Type of Solution to It, and a Method of Ethics
Index of Names