Hauntology (a portmanteau of haunting and ontology) is a neologism introduced by French philosopher Jacques Derrida in his 1993 book Spectres of Marx. As a philosophical concept, it refers to the return or persistence of elements from the past, as in the manner of a ghost. It has since been invoked in fields such as visual arts, philosophy, electronic music, politics, fiction and literary criticism. Derrida used the term to refer to the atemporal nature of Marxism and its tendency to "haunt Western society from beyond the grave." It describes a situation of temporal and ontological disjunction in which presence is replaced by a deferred non-origin. The concept is derived from his deconstructive method, in which any attempt to locate the origin of identity or history must inevitably find itself dependent on an always-already existing set of linguistic conditions. Despite being the central focus of Spectres of Marx, the word hauntology appears only three times in the book, and there is little consistency in how other writers define the term. In the 2000s, the term was applied to musicians who were said to explore ideas related to temporal disjunction, retrofuturism, cultural memory, and the persistence of the past.