Time Travel, Parahistory and the Past Artefact Dilemma

Abstract

In 1987, Roy Sorensen coined the term ‘parahistory’ to denote the study of genuinely anachronistic artefacts delivered by time travel.1 ‘Parahistory’ would thus stand to history rather as parapsychology is claimed to stand to psychology, i.e. the parahistorian would study historical data that were obtained through channels that orthodox science does not recognise. How might one establish credentials as a time traveller? What sort of evidence could a time-traveller point to in support of claims that would presumably command a great deal of scepticism? While successful predictions might be one confirmatory tool, supporting evidence needn't take the form of predictions. (Although Sorensen offers an intriguing argument that a Humean about miracle-testimony would be obliged to reject any testimony to the occurrence of time travel.) Perhaps artefacts that time travellers retrieve from other times (past or future) could usefully supplement testimonial or predictive evidence for the parahistorian. However, this paper will argue, any appeal to past-artefactual evidence for parahistorical claims faces a dilemma that threatens to undermine its value: appeals to past-artefact evidence must either collapse into appeals to predictive evidence or see their value diminished by such past artefacts' necessarily exhibiting contradictory indicators of age and period.

The Close Possibility of Time Travel

“…Physical possibility is only one such candidate (e.g., Klimov's Come and See is physically possible whilst Lucas's Star Wars is not); moreover, in the context of science fiction, it is unlikely to be of much interest. Certainly, when it comes to time travel, broader modalities are normally our focus, e.g., logical possibility [1,5,[12][13][14][15][16][17], metaphysical possibility [3,[18][19][20][21][22][23], conceptual possibility [24], or absolute possibility [25,26].…”

“…441, 454). Certainly, other philosophers have explicitly investigated the possibility of specific time travel fictions, as well as the possibility of tropes from those fictions [3][4][5][6][7]. This paper is in that same vein, focusing on the possibility of various tropes common to time travel fiction.…”

Artefacts from tomorrow: Future dilemmas of the parahistorian

“…Rarer are discussions of evidential problems for time travel. Richmond (2010a) claims evidence derived from past‐derived parahistorical artefacts, as a supplement to testimonial or predictive evidence for time travel, either disintegrates under the impact of contradictory indicators or collapses into testimonial evidence. This paper claims future artefacts are more evidentially problematic than past ones.…”

“…Parahistorical evidence must distinguish an artefact's “period indicators” from its “age indicators”: the former reflect the artefact's time of origin and the latter reflect how much elapsed time the artefact has registered since it came into existence. (See Richmond, 2010a, p. 371.)…”

“…So overall the evidential value of future‐derived parahistorical artefacts qua artefacts seems, like that of their past‐derived cousins (cf. Richmond, 2010a, p. 373), negligible taken in isolation, i.e. if the claims they are meant to support are not bolstered by testimonial evidence and/or successful predictions, etc.…”