There are five people on the track and a runaway trolley that will hit them, and you are on a footbridge over the track with a large person whose body can stop the trolley in its tracks. Should you push the large person to his death to save the five on the track? Using hypothetical cases and questions about them to elicit judgments is a prominent method of analytic philosophy to discover modal or necessary truths – truths about what must be the case. The method is used to consider what action is right, whether free will requires the ability to do otherwise, whether knowledge requires something more than justified true belief, whether the mind must depend on the body, and so on. In his new book Philosophy Within Proper Bounds (Oxford University Press, 2017), Edouard Machery draws on more than a decade of experimental philosophical and psychological research by himself and others to argue that the method of cases should be shelved. On his view, variations across study subjects by demographic factors such as age and by presentation effects such as the order in which cases are presented show that the results of the method are fundamentally unreliable, and that we should suspend judgment about their results. Machery recommends instead a reorientation of the mainstream analytical philosophical tradition: philosophers should limit themselves to modally modest questions, and they can engage in a modified psychological form of conceptual analysis in which we seek to understand what sets of automatic inferences individuals or groups tend to draw, rather than seeking conceptually necessary truths.
Carrie Figdor is professor of philosophy at the University of Iowa.