Experimental philosophy is not a philosophy, it is a method that is supposed to contribute to philosophical inquiry. Characteristically, experimental philosophers use empirical techniques to investigate philosophically significant intuitions about cases. An intuition, in this context, is a spontaneous judgement a person makes about a case with little or no conscious reason for their judgement.
Intuitions play a key role in much philosophical theorizing. The attempt to provide a conceptual analysis or definition for important philosophical concepts, e.g. knowledge, meaning, responsibility, has long been a major theoretical concern in philosophy. One prominent philosophical view holds that the meaning of our concepts is given by the folk theory (or set of common-sense beliefs) in which the concepts are embedded. Intuitions about cases are thought to reveal the contours of the folk theory and the meaning of the concept. As a result, in pursuing conceptual analyses, many philosophers rely on intuitions about cases to descry the folk theories in which those concepts are embedded.
In addition to their role in conceptual analysis, philosophers invoke intuitions as evidence for substantive philosophical claims, perhaps in much the same way as empirical scientists invoke observation as evidence. For instance, the intuition that it is wrong to push one man in front of a speeding trolley to save five others is invoked as evidence that utilitarianism does not give the right theory of how we ought to act. Similarly, intuitions are used to support substantive claims about knowledge, meaning and responsibility.
When philosophers use intuitions - whether in the service of conceptual analysis or in the effort to establish a more substantive philosophical claim - the traditional methodology looks a priori. That is, one arrives at one’s judgements without relying on evidence from sensory perception. For instance, to analyse the concept intentional a philosopher might consult their intuitions about whether the concept applies in various actual and possible circumstances, and a condition of adequacy upon the definition is that it best conforms to these intuitions. In contrast, experimental philosophers use experimental techniques to study intuitions about philosophically important concepts.
Psychology and the Use of Intuitions in Philosophy