Thought Experiments and Intuition Pumps in Moral and Political Philosophy

Imaginary cases are used a great deal in moral and political philosophy. They are used to test or critique moral theories by holding those theories up to examination in the light of our intuitions or considered judgements about right action in imaginary situations. They are part and parcel of the process of reflective equilibrium by which we standardly modify both our theories and our intuitions in the light of what each can tell us about the other. Such cases are often used in science too: Albert Einstein often used imaginary situations when making his radical advances in physics. In this paper I make a distinction between thought experiments and intuition pumps. The former are deductive and, given the assumptions, demonstrate some conclusion. Often, though not always, the conclusion is that some previously held theory could not be true as it contains a contradiction. An intuition pump is inductive. It invites a conclusion given a scenario, and the intuition so inducted (or pumped) is then used to critique a theory or generate a conclusion. Not everyone shares the same intuitions, and they have been shown to be culturally and socially bound. Some cases can be used in either sense. Mathematicians interpret toy games, such as the Prisoners’ Dilemma, as thought experiments; philosophers have often used them as intuition pumps. Thought experiments are vital elements of scientific thought. Intuition pumps are more problematic. The epistemic status of their conclusions is unclear and their proper usage needs to be handled carefully. The paper considers the epistemic status of our intuitions as pumped, and considers the proper and improper use of intuition pumps in moral and political thought.