 He also discusses the uncanny nature of Otto Rank's concept of the "double".Freud specifically relates an aspect of the "Uncanny" derived from German etymology.By contrasting the German adjective "unheimlich" with its base word "heimlich" ("concealed, hidden, in secret"), he proposes that social taboo often yields an aura not only of pious reverence but even more so of horror and even disgust, as the taboo state of an item gives rise to the commonplace assumption that that which is hidden from "public eye" (cf.