Thought Experiments in Ethics

Abstract

Thought experiments have been part of the philosopher's toolkit when exploring ethical issues since the very beginnings of philosophy. One need only look to Book 1 of Plato's 'Republic' to find a telling example of a thought experiment at work. Therein Plato asks us, in order to focus our attention on the problem of what reasons there are for acting morally, to imagine a ring that enables its wearer to become invisible and thereby to perpetrate all sorts of mischief. This is but one of many instances of their use to be found in the ethics literature. Some of the more famous recent examples of thought experiments in ethics, which vary widely with respect to their realism, include Philippa Foot's notorious "trolley problem," Bernard Williams' story of Jim and the Indians, and Judith Jarvis Thomson's "famous violinist" (Foot 1978; Smart and Williams 1973; Thomson 1971). However, for many newcomers to philosophical ethics the use of such stories, which often involve highly bizarre and implausible scenarios, is disconcerting. Why do philosophers, in the pursuit of ethical truth, make use of what are often fanciful stories? In this essay, we shall explore the use of thought experiments in ethics and attempt to provide some justifications for their use. What role do they play in ethical reasoning? How might it be that an imaginary tale can illuminate philosophical issues? We shall also consider a number of objections to the central role that they play in much moral theorizing. Unsurprisingly, there are many philosophers who object to their use; some have argued that they are misleading because of either the under-description required or the generalization they encourage. Others have objected that many of these thought experiments are immoral since they require us to imagine scenarios that should not be contemplated.