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Although Greg argued that an editor should be free to use his judgment to choose between competing substantive readings, he suggested that an editor should defer to the copy-text when "the claims of two readings ... appear to be exactly balanced. ... In such a case, while there can be no logical reason for giving preference to the copy-text, in practice, if there is no reason for altering its reading, the obvious thing seems to be to let it stand." The "exactly balanced" variants are said to be indifferent.
Textual criticism