 Because of the breadth of the topic, this entry focuses exclusively on contemporary discussions of imagination in the Anglo-American philosophical tradition. For an overview of historical discussions of imagination, see the sections on pre-twentieth century and early twentieth century accounts of entry on  mental imagery;  for notable historical accounts of imagination, see corresponding entries on  Aristotle,  Thomas Hobbes,  David Hume,  Immanuel Kant, and  Gilbert Ryle;  for a more detailed and comprehensive historical survey, see Brann 1991; and for a sophisticated and wide-ranging discussion of imagination in the phenomenological tradition, see Casey 2000.