What exactly is a philosophical intuition? And what makes such an intuition reliable, when it is reliable? This paper provides a terminological framework that is able answer to the first question, and then puts the framework to work developing an answer to the second question. More specifically, the paper argues that we can distinguish between two different "evidential roles" which intuitions can occupy: under certain conditions they can provide information about the representational structure of an intuitor's concept, and under different conditions, they can provide information about whether or not a property is instantiated. The paper describes two principles intended to capture the difference between the two sets of conditions---that is, the paper offers a principle that explains when an intuition will be a reliable source of evidence about the representation structure of an intuitor's concept, and another principle that explains when an intuition will be a reliable source of evidence about whether or not a property is instantiated. The paper concludes by briefly arguing that, insofar as philosophers are interested using intuitions to determine whether or not some philosophically interesting property is instantiated by some scenario (for instance, whether knowledge is instantiated in a Gettier-case), the reliability of the intuition in question does not depend on whether or not the intuition is widely shared.