Ur-Text

Entertainment / Literature / Ur-Text: A hypothetical 'best' version of a lost literary text based on correlating later manuscripts and examining the differences between them. An Ur-text is not an actual physical manuscript we can examine or see in a museum, but rather an imaginary reconstruction of one that must have existed at some past point in time based on available evidence. This reconstruction cannot be absolutely certain, but it is a useful thought experiment for helping editors decide between textual variants when creating an edition of a literary work. Later manuscripts and printed texts often exist in literary families, with later versions adapted from earlier ones. Scribal corruption, printing errata, authorial revision, and deliberate bowdlerization or alteration by later editors can result in textual variants (slightly differing versions of the same basic text). It isn't always clear which of these versions is most accurate.
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Stemma

Entertainment / Literature / Stemma: A record or diagram similar to a family tree showing the connections between manuscripts of a given literary work. See discussion under Ur-text. (plural stemmata) MORE

Source

Entertainment / Literature / Source: (1) An earlier work of literature or folklore used as the basis of a later work. Scholars use the term source only when it is clear that one of the manuscripts or one piece of oral transmission influe MORE

Q-Text

Entertainment / Literature / Q-Text: The term for a hypothetical ur-text or source manuscript that served as the source for the synoptic gospels (i.e., Matthew, Mark, and Luke), but which did not influence John. The abbreviation 'Q' come MORE