A Syntopicon: An Index to The Great Ideas (1952) is a two-volume index, published as volumes 2 and 3 of Encyclopædia Britannica’s collection Great Books of the Western World. Compiled by Mortimer Adler, an American philosopher, under the guidance of Robert Hutchins, president of the University of Chicago, the volumes were billed as a collection of the 102 great ideas of the western canon. The term “syntopicon” was coined specifically for this undertaking, meaning “a collection of topics.” The volumes catalogued what Adler and his team deemed to be the fundamental ideas contained in the works of the Great Books of the Western World, which stretched chronologically from Homer to Freud. The Syntopicon lists, under each idea, where every occurrence of the concept can be located in the collection’s famous works.