Framing Effect in the Trolley Problem and Footbridge Dilemma.

The present study investigated the effect of dilemma type, framing, and number of saved lives on moral decision making. A total of 591 undergraduates, with a mean age of 20.56 (SD = 1.37) were randomly assigned to 12 groups on the basis of a grid of two dilemma types (the trolley problem or the footbridge dilemma) by three frames (positive, neutral, or negative frame) by two different numbers of workers (5 or 15 people). The main effects of dilemma type, frame, and number of saved workers were all significant. The interaction of dilemma type and number of saved workers and the interaction of the three independent factors were significant. Results indicated that moral judgment is affected by framing. Specifically, people were more inclined to utilitarianism in the positive or neutral frame and more inclined to intuitionism in the negative frame. Furthermore, this effect can be moderated by dilemma type and number of saved lives. Implications of our results are discussed.