Judith Jarvis Thomson; Killing, Letting Die, and The Trolley Problem, The Monist, Volume 59, Issue 2, 1 April 1976, Pages 204–217, https://doi.org/10.5840/monis.

This discussion attempts to show that the elusive solution to the trolley problem lies hidden in the solution to another perennial problem in moral philosophy: the ducking puzzle. The key to solving the ducking puzzle is an important, but overlooked, exception to our obligation not to harm others, an exception for , which, it is argued here, is also the key to solving the trolley problem.