Experimental philosophy is an emerging field of philosophical inquiry that makes use of empirical data—often gathered through surveys which probe the intuitions of ordinary people—in order to inform research on philosophical questions. This use of empirical data is widely seen as opposed to a philosophical methodology that relies mainly on a priori justification, sometimes called "armchair" philosophy, by experimental philosophers. Experimental philosophy initially began by focusing on philosophical questions related to intentional action, the putative conflict between free will and determinism, and causal vs. descriptive theories of linguistic reference. However, experimental philosophy has continued to expand to new areas of research.
Disagreement about what experimental philosophy can accomplish is widespread. One claim is that the empirical data gathered by experimental philosophers can have an indirect effect on philosophical questions by allowing for a better understanding of the underlying psychological processes which lead to philosophical intuitions. Others claim that experimental philosophers are engaged in conceptual analysis, but taking advantage of the rigor of quantitative research to aid in that project. Finally, some work in experimental philosophy can be seen as undercutting the traditional methods and presuppositions of analytic philosophy. Several philosophers have offered criticisms of experimental philosophy.
Though, in early modern philosophy, natural philosophy was sometimes referred to as "experimental philosophy", the field associated with the current sense of the term dates its origins around 2000 when a small number of students experimented with the idea of fusing philosophy to the experimental rigor of psychology.
While the philosophical movement Experimental Philosophy began around 2000 (though perhaps the earliest example of the approach is reported by Hewson, 1994), the use of empirical methods in philosophy far predates the emergence of the recent academic field. Current experimental philosophers claim that the movement is actually a return to the methodology used by many ancient philosophers. Further, other philosophers like David Hume, René Descartes and John Locke are often held up as early models of philosophers who appealed to empirical methodology.