Question
What is a thought experiment and why are they useful?
Answer
A thought experiment is a hypothetical scenario which is designed to isolate and test a particular principle. Sometimes they are exploratory, and are intended to provoke responses and spur debate, or sometimes they can be designed to present a case that is particularly challenging for a theory to account for. They do not have to be plausible – in fact, many thought experiments are extremely outlandish and convoluted – but they must be conceivable.
As an example, a common thought experiment is the ‘trolley problem’, wherein the imaginer is asked whether to divert the course of a runaway train to prevent the deaths of multiple people at the expense of causing the death of just one. The intention of this particular experiment is to isolate the respondent’s intuitions with regard to the relative moral weights of killing and letting die when set against the moral weight of differing consequences.
Thought experiments are useful because they provide an opportunity to test theories against the most extreme cases that they can be expected to account for, the implication being that if they can accommodate these outliers, they are robust enough to deal with anything.
