 In the last ten to fifteen years, there has been an explosion of interest in research involving the scientific or empirical investigation of intuitions of philosophical interest. Such projects are now frequently grouped under the rubric of “experimental philosophy.” (For general characterizations of experimental philosophy see Knobe and Nichols 2008, Appiah 2008, and Nadelhoffer and Nahmias 2007.) At least four broadly-individuated projects in experimental philosophy can be distinguished.